a fuel transfer coupling according to the present invention comprises an on - board portion which is in fluid contact with the gasoline tank on a motorized vehicle such as a race car , and a remote portion which is in fluid contact with a source of liquid hydrocarbon fuel that is to be delivered to the gasoline tank of the motorized vehicle . the on - board portion may be referred to as the male adapter and the remote portion of the coupling may be referred to as the female adapter , for convenience . referring to the drawings , and initially to fig1 there is shown the on - board portion of a fuel transfer coupling according to the invention in an exploded view , including all of its various components , which are described forthwith . in fig2 is shown a perspective view of the male adapter base 4 . the male adapter base 4 includes a central bore 34 through which fuel is intended to flow . the central bore 34 has a first end portion which is adapted to be connected to the inlet pipe of a fuel tank , and a second end portion which extends into said adapter base and terminates at a point within the male adapter base . disposed about the central bore 34 is a shrouding enclosure 36 which forms an envelope around the central bore portion 34 for the purpose of allowing the travel of gas or air vapor through the various holes 33 disposed in the planar top surface 40 of the male adapter base , wherein the holes 33 are in fluid contact with the outlet portion 35 of the vapor tube 20 . thus , this assembly is similar to a condenser as used in the chemical arts , which consists of a tube having a water jacket about it , with an inlet and outlet for the cooling water , and a tube disposed therethrough which the vapor to be condensed is caused to pass . in the present instance , the central bore 34 is surrounded by the shrouding enclosure 36 , which has as its “ inlet ”, the various holes 33 , and which has as its “ outlet ”, the vapor tube 20 . there is a planar flange portion 42 having a plurality of holes 44 disposed through it along its periphery for the purpose of fastening the male adapter base to other components of this portion of the coupling . the plane of the flange portion 42 is slightly below the plane of the top surface 40 , and at the point of intersection of these two features there is thus caused to exist an elevation 38 , upon which an o - ring seal may be mounted for sealing the surfaces in the finished assembly . there is a circumferential ledge 37 onto which a flow cone 58 is mounted , as is described later herein . the wall w of the bore above the circumferential ledge 37 is also shown . in fig3 is shown an overhead view of the male adapter base 4 , including the central bore 34 flange 42 , holes 44 , vapor tube 20 , holes 33 , circumferential ledge 37 , and o - ring seal 46 in its location at the elevation at 38 as shown in fig2 . fig4 shows a perspective view of the male adapter cover 2 , having an outer wall 24 , top surface 3 , and flange portion 26 , wherein the flange portion 26 includes a plurality of holes 28 disposed along its periphery for connection to the male adapter base 4 once all of the components have been properly assembled , using conventional fasteners . there is also a beveled edge 30 , which is shown in fig6 as well . fig5 shows a side elevation view of the male adapter cover 2 , including outer wall 24 and flange 26 . fig6 shows a bottom view of the male adapter cover 2 , including its flange 26 , plurality of holes 28 , annular groove 19 which extends about the hole 1 adjacent to the flange 26 and is adapted to receive the o - ring seal 46 in a sealing relationship in the completed assembly . there is also a beveled edge 30 . fig7 shows the internal housing 18 , which is reminiscent of a hollow shell having an open top portion t and an open bottom portion b , and a hollow interior space within the confines of its walls . there is a flat top surface 48 , a sloping shoulder portion 49 which includes an o - ring seal 50 , which o - ring seal 5 is disposed to seal between the sloping shoulder 49 and the beveled edge 30 from fig4 and 6 previously . there is also an o - ring seal 52 disposed along the bottom skirt portion 51 as well , for sealing the skirt portion 51 against the wall portion w of the bore in fig2 . thus , the skirt portion 51 of the internal housing 18 is slidably disposed within a circumferential slot which is defined by the wall w that is adjacent to the circumferential ledge 37 and the wall portion 64 of the flow control cone 6 when the flow control cone is in its position on the circumferential ledge 37 . the skirt portion 51 provides a travel stop against planar top surface 40 . fig8 shows a side elevation view of the internal housing 18 and depicts the locations of the top surface 48 , sloping shoulder 49 , o - ring seal 50 , skirt 51 , and o - ring seal 52 . fig9 shows a perspective view of the flow control cone 6 component . the flow control cone 6 includes a funnel - shaped cone element 58 , which is held rigidly in place in the center of an outer ring 62 ( which has a wall portion 64 ) by means of cone supports 60 which are welded or otherwise attached by known conventional means , such as integral casting , etc ., to the cone and inner portion of the wall portion 64 of the outer ring 62 . there is also a poppet guide bore 54 disposed at the apex of the cone , and a space 59 disposed between the cone 58 and the outer ring 62 . fig1 is a side elevation view of the flow control cone 6 showing the cone 58 , wall portion 64 , and the outer ring 62 . the cone supports 60 are also shown . fig1 shows a bottom view of the flow control cone 6 showing the poppet guide bore 54 , wall portion 64 , outer ring 62 , cone supports 60 , space 59 , and cone 58 . the diameter of the wall portion is slightly less than that of the internal diameter of the bottom portion b of the internal housing 18 shown in fig7 , which enables the skirt portion 51 of the internal housing to reside atop the outer ring 62 of the flow control cone 6 after the flow control cone 6 has been placed in position on the circumferential ledge 37 of fig2 . fig1 shows a perspective view of the top of the flow control cone 6 including the poppet guide bore 54 having an outer wall 56 . there is a flat portion 57 which serves as the seat for the poppet spring 8 ( fig1 ). also shown is cone 58 , cone supports 60 , outer ring 62 , and wall portion 64 . fig1 a shows a perspective view of the upper portion of the poppet 10 which includes a flat top surface 70 , and an o - ring seal 72 disposed on the upper shoulder 80 ( fig1 b ). there is a poppet stem 68 which is preferably of a tri - lobe cross - section as later shown . there is a vent disc 14 disposed in a recess in the face of the flat top surface 70 , which is held in place by retainer ring 16 , which retainer ring 16 is held in position by means of machine screws threaded through the flat top surface . the vent disc 14 in one embodiment includes a hole 15 that passes through the vent disc . the spring 12 mechanically biases the disc 14 onto its seat . according to an alternate form of the invention , the hole 15 may be disposed through the wall of the male adapter cover 2 . fig1 b is a side elevation view of the poppet 10 , showing the upper shoulder 80 of the poppet 10 , lower shoulder 81 of the poppet 10 , o - ring seal 72 , and poppet stem 68 . fig1 shows a perspective view of the underside of the poppet 10 which includes the lower shoulder 81 , flat bottom surface 83 , o - ring seal 72 , vent disc 14 having hole 15 , spring 12 , machine screw bottoms 78 , poppet stem 68 , and stem supports 69 . the spring 12 is disposed between the vent disc 14 and the poppet stem 68 so as to maintain a mechanical bias on the vent disc 14 in a direction towards the flat top surface 70 from fig1 a . fig1 shows a bottom view of the poppet 10 including the stem supports 49 , poppet stem 68 , vent disc 14 , lower shoulder 81 , and flat bottom surface 83 . the circle labeled d 1 is of such a diameter as to be just slightly larger than the diameter d 2 of the top portion of the cone 58 ( fig1 ) so that the skirt of the poppet 81 lines up with the top portion of the cone 58 to promote a smooth fuel flow . the poppet stem 68 is of such diameter as to form a snug fit which allows in and out motion of the poppet within the poppet guide bore 54 . fig1 shows a side view of the male adapter 700 in its final assembled form , when all of the components shown in fig1 and as previously described herein are contained within the male adapter cover 2 and the male adapter base in their proper design configuration . to assemble the male adapter 700 , one begins by placing the male adapter base 4 on a flat surface . next , the flow cone 6 is placed into position so that the outer ring 62 of the flow cone 6 rests on the circumferential ledge 37 , so that the poppet spring seat 57 is facing upwards , as shown in fig1 . next , the poppet 10 ( including the spring 12 , vent disc 14 , and retaining ring 16 ) is inserted into the internal housing 18 from the bottom b ( fig8 ) so that the o - ring seal 72 contacts the inner wall of the internal housing 18 at a location on the interior of the sloping shoulder 49 , which is a bevel 99 shown in fig7 that extends around the inner circumference of the internal housing so as to completely contact the o - ring seal 72 . next , the poppet spring 8 is placed on the spring seat 57 , and the internal housing 18 ( with poppet 10 inside it ) is then placed into position so that the skirt portion 51 rests atop the outer ring portion 62 of the flow control cone 6 , against the pressure of the poppet spring . finally , the male adapter cover 2 is placed over the internal housing and the fasteners are secured to connect the flanges on the male adapter cover 2 and the male adapter base 4 , to provide the assembled male adapter 700 as shown in fig1 . fig1 shows a top view of the assembled male adapter 700 , showing the respective positions of the vent disc 14 , vent hole 15 , retaining ring 16 , vapor tube 20 , flange 26 , flat top surface 48 of the internal housing 18 , flat top surface 70 of the poppet 10 , top surface 3 of the male adapter cover 2 ( fig4 ), and the important gap 7 between the outer perimeter of the flat top surface 48 of the internal housing 18 and the inner perimeter of the top surface 3 of the male adapter cover 2 . the gap 7 is important , as it is through this gap that air passes during a refueling operation , to allow the escape of headspace air in the fuel tank to compensate for the volume of fuel delivered during the refueling operation . as the flat top surface 70 of the poppet is depressed slightly , at first , against the pressure of the poppet spring 8 , both the poppet 10 and the internal housing 18 move into the assembly as a whole , until the skirt portion 51 has bottomed out against the face 40 of the body 4 . the movement of the internal housing 18 to its bottomed out position opens a space in the gap at 7 between the inner wall of the male adapter 2 and the internal housing 18 by releasing the contact between the o - ring seal 50 and the beveled edge 30 . this slight depressing of the flat top surface 48 of the internal housing 18 causes a fluid connection to exist between the vapor tube 20 and the gap 7 at the top portion of the assembly where the o - ring seal 50 has separated from the beveled edge 30 , through the plurality of holes 33 in the male adapter base 4 . further depressing of the flat top surface 70 of the poppet 10 opens a space s between the outer periphery of the top surface 70 of the poppet 10 and the internal wall of the internal housing 18 , as shown in fig1 , thus enabling a liquid fuel to pass through the inner volume of the internal housing , through the open space 59 in the flow control cone 6 and through the central bore 34 , which is connected to the inlet pipe on the vehicle &# 39 ; s fuel tank . the vapor tube 20 is connected to a hose which is in fluid contact with the headspace gas within the fuel tank . thus , by depressing the flat top surface 70 of the poppet 10 , a fluid communication between the headspace gas in the fuel tank and the gap at 7 is first caused , and secondly a pathway is opened to the fuel tank for fuel to flow in through central bore 34 , from a location at the top of the poppet in the closed condition . this is because the poppet spring 8 biases the poppet upwards ; however , the poppet 10 is located within the internal housing 18 but the head of the poppet has a larger diameter than the diameter of the beveled edge 99 just beneath the top surface 48 of the internal housing 18 in which it is contained , which thus also causes the internal housing 18 to be biased upwards . the internal housing 18 is held in position within the male adapter cover 2 because the diameter of the sloping shoulder 49 of the inner housing 18 is larger than that of the beveled edge 30 in the male adapter cover . this is why the male adapter assembly 700 can only be assembled as taught herein . fig1 shows the underside view of the male adapter assembly 700 when the poppet 10 is not depressed , and fig2 shows the underside view of the assembly 700 while the poppet 10 is depressed , showing the movement of the poppet stem 69 with respect to the outer wall 56 . fig2 is a top perspective view of the male adapter assembly 700 , and fig2 is a bottom view of the male adapter assembly 700 . a fuel transfer coupling according to the present invention comprises a remote portion which is in fluid contact with a source of liquid hydrocarbon fuel that is to be delivered to the gasoline tank of the motorized vehicle . the remote portion may be thought of as a female adapter owing to its being adapted to receive the male portion of the coupling already described herein . the female adapter , in one preferred form of the invention , is preferably disposed at the exit point of a fuel from a portable , remote fuel reservoir . referring to the drawings , and particularly to fig2 there is shown the remote portion of a fuel transfer coupling according to the invention in an exploded view , including all of its various components , which are described forthwith . fig2 shows a side elevation view of a female adapter base 164 according to the invention , including the top portion of the central conduit 166 t , bottom portion of the central conduit 166 b , shrouding enclosure 170 vapor tube 172 , o - ring seal 168 , and raised surface 171 . fig2 shows a perspective view of the upper portion of the female adapter base 164 according to the invention , including the raised surface 171 , shrouding enclosure 170 , outer flange 180 having a plurality of holes 182 disposed thereon , holes 174 , vapor tube 172 , top portion of the central conduit 166 t having a flat top surface 184 , o - ring seal 168 , and a retaining fastener 176 disposed in a boss 177 held centrally within the interior of the central conduit by means of a plurality of fastener boss supports 178 , which are affixed to the inner surface of the wall of the central conduit by conventional means , such as a weld . retaining fastener 176 is shown with its threads visible . fig2 shows a top view of the female adapter base 164 according to the invention , including the central conduit , raised surface 171 , holes 174 , vapor tube 172 , top surface 184 , flange 180 , holes 182 , fastener boss supports 178 and retaining fastener 176 . thus , the female adapter base 164 includes a central conduit 166 through which fuel is intended to flow . disposed about the central conduit is a shrouding enclosure 170 which forms an envelope around the central conduit for the purpose of allowing the travel of gas or air vapor through the various holes 174 disposed in the raised surface 171 of the female adapter base , wherein the holes 174 are in fluid contact with the outlet portion 187 of the vapor tube 172 . thus , this assembly is similar to a condenser as used in the chemical arts , which consists of a tube having a water jacket about it , with an inlet and outlet for the cooling water , and a tube disposed therethrough which the vapor to be condensed is caused to pass . in the present instance , the central conduit is surrounded by the shrouding enclosure 170 , which has as its “ inlet ”, the various holes 174 , and which has as its “ outlet ”, the vapor tube 172 . fig2 shows a perspective view of a female adapter cover 144 according to the present invention , which is shaped in the form of a hollow cylindrical shell , reminiscent of a cylinder sleeve . the female adapter cover includes a smooth bore 196 along its length dimension , except for a raised band 194 at the top , which raised band has a slightly less inner diameter than the smooth bore 196 . there is an o - ring seal 148 which is disposed in an annular slot at the upper end of the female adapter cover , which o - ring provides a seal around the outer surface of the male adapter cover 2 when the male adapter cover is inserted into the female adapter cover 144 . there is a top surface 146 and a flared bottom 150 . fig2 shows a top view of the female adapter cover 144 , including the top surface 146 and the o - ring seal 148 . fig2 shows a bottom view of the female adapter cover 144 , including flared bottom 150 and a plurality of threaded holes 152 disposed circumferentially about the lower flared portion , which holes are adapted to receive a fastener that also passes through the holes 182 in the female adapter base 164 , which are in the same configuration and spacing on both the female adapter cover 144 and female adapter base 164 . the diameter d 3 of the inner bore 196 of the female adapter cover 144 is just slightly larger than the diameter of the raised surface 171 , so that the female adapter cover 144 may be securely fit over the female adapter base 164 . fig3 a shows a moveable collar 102 according to the present invention , which is shaped as a hollow cylinder . the moveable collar 102 is intended to be slidably disposed within the smooth bore 196 of the female adapter cover 144 . the moveable collar 102 includes a groove 108 in which is housed an o - ring seal 130 , which o - ring seals the outer surface of the moveable collar 102 within the smooth bore 196 of the female adapter cover 144 . there is a flat top surface 106 , and a plurality of slots 104 which pass through the wall of the moveable collar and may thus be regarded as holes . on the inside wall of the moveable collar 102 , there is a flat recessed surface 112 that is disposed between beveled edge 114 and bevel 110 . surface 113 extends annularly about the inside diameter of the moveable collar 102 , and has itself an inside diameter which is smaller than the inside diameter of the flat recessed surface 112 . the surface 115 extends annularly about the inside diameter of the moveable collar 102 and has its own inside diameter which is less than that of surface 113 . thus , going from surface 113 to surface 112 , there is a bevel 110 . then , going from surface 112 to surface 115 , there is a beveled edge 114 . fig3 b shows a side elevation view of the moveable collar 102 element of the invention , including the slots 104 , flat top surface 106 , and groove 108 . fig3 is a top view of the moveable collar 102 element of the invention , including the flat top surface 106 . fig3 shows a bottom view of the moveable collar 102 element of the invention , including the beveled edge 114 and holes 117 which are drilled from the bottom surface of the moveable collar to the floor portion of each of the slots 104 , so as to enable insertion of springs into the holes 117 . fig3 shows a perspective view of the bottom of the moveable collar 102 , including the slots 104 and groove 108 . there is also shown surface 115 , beveled edge 114 , holes 117 , surface 112 , surface 113 , flat surface 119 , wall 203 , and flat surface 201 . the flat surface 119 accommodates a retaining ring 190 ( fig2 ) having same diameter as said flat surface 119 , to retain in their position springs which have been placed into the holes 117 . the springs are then held in place by a retaining ring fastened to flat surface 119 , either by interference fit , an adhesive substance , or other conventional means . there is also a flat bottom surface 201 . fig3 shows a seal ring 116 element of the invention , which is preferably metallic in construction , as are all of the other elements of the couplings of the present invention . the seal ring includes a hollow interior space 207 . there is a flat top surface 118 which includes an o - ring seal embedded in an annular groove that is present on the flat top surface 118 . there is a beveled surface 132 , which is reminiscent of a valve - seat in an automotive cylinder head , and which beveled surface functions as a seat for the valve center 154 as later described herein . there is a shoulder portion 120 which includes an o - ring seal 122 annularly disposed thereon . there is also a lower shoulder 134 , and a skirt portion 128 , as well as a smooth bore 312 . these elements are shown in fig3 as well , in addition to threaded holes 126 which are drilled into the seal ring 116 at a band portion 124 which circumscribes the seal ring . there are a plurality ( preferably 4 ) of holes 126 spaced around the perimeter of the seal ring 116 which correspond in position to the slots 104 in the moveable collar 102 . the centerlines of the bores of the threaded holes 126 are perpendicular to the centerline of the seal ring 116 itself . there is also a flat portion 192 on the underside of the seal ring which functions as a seat for the spring 186 ( fig2 ). fig3 is a top view of the seal ring 116 , showing the respective positions of the beveled surface 132 , flat top surface 118 , o - ring seal 130 , shoulder 120 , and o - ring 120 . fig3 shows the collar / seal ring assembly 136 . according to the invention , the seal ring 116 is moveably held in place within the moveable collar 102 . this is done by first inserting a spring 140 into each of the holes 117 in the underside of the moveable collar 102 , and then securing them in place by placement of spring retaining ring 190 ( fig2 ) onto the flat surface 119 , such as by using an epoxy resin . this causes the springs to be partly visible in the slots 104 and partially embedded within the hole 117 between the bottom of the moveable collar and the bottom of the slots 104 . a slight forcing of the springs 140 downward enables one to insert a screw 138 ( whose threads match the holes 126 on the outer band of the seal ring 116 into the slot between the top of the spring 140 and the top portion of the oval or elongate slot 104 . when four screws are inserted into the four slots 104 in such fashion , the seal ring 116 may then be placed into the interior of the moveable collar 102 so that the four screws 138 are engaged in the threads in the holes 126 . a more preferred means for assembly is to first assemble o - ring 122 to seal ring 116 . subsequently , the seal ring 116 is fitted inside the moveable collar 102 , and then the screws 138 are inserted through the slots in the moveable collar 102 into threaded holes 126 in 116 . then the springs 140 are inserted into the holes 117 and the retainer 190 is fitted into the groove in the moveable collar 102 . such a construction yields the arrangement shown in fig3 in which the seal ring 116 is held within the moveable collar 102 in such fashion that motion of the seal ring 116 within the moveable collar 102 is permitted in the direction of the centerline , but downward , and against the pressure of the springs 140 applied on each of the screws 138 . such a motion downwards pushes the seal ring 116 downward , releasing the contact between the o - ring 122 and the beveled edge 114 , thus opening up an annular space located at the gap at 142 . upon release of downward pressure on the seal ring 116 , the force of the springs 140 force the seal ring 116 back in an upwards direction , forcing the o - ring 122 to sealably engage the beveled edge 114 . also shown in fig3 is the flat top surface 106 , flat top surface 118 , o - ring seal 130 , beveled surface 132 , and o - ring seal 188 disposed in groove 108 . although the screws 138 are used to secure the seal ring 116 in its position within the moveable collar 102 , any other functionally equivalent equatorially - located protrusions from the seal ring are suitable for use in this regard , including without limitation , pins welded into place . fig3 shows a side view of the collar / seal ring assembly 136 , showing the respective positions of the flat top surface 118 , flat top surface 106 , groove 108 , springs 140 and screws 138 . the bottom of the assembly is denoted as b . fig3 shows an overhead view of the collar / seal ring assembly 136 , showing the respective positions of the flat top surface 118 , o - ring 130 , gap 142 , flat top surface 106 , and beveled surface 132 . fig4 a shows a top view of the valve center 154 of the present invention having a flat top surface 156 . fig4 b shows a perspective view of the underside of valve center 154 of the present invention , showing the stem portion 158 which has a threaded hole 160 at its bottom portion and an o - ring seal 162 disposed annularly about the valve center . fig4 c shows a side perspective view of the valve center element 154 , showing the respective positions of the stem 158 and o - ring seal 162 and flat top surface 156 . fig4 shows a side view of the female adapter 701 in its final assembled form , when all of the components shown in fig2 and as previously described herein are contained within the female adapter cover 144 and the female adapter base 164 in their proper design configuration . to assemble the female adapter 701 , one begins by placing the female adapter base 164 on a flat surface so that the bottom of the central conduit 166 b and vapor tube 172 rest on the flat surface . next , the spring 186 is placed in position around the top portion of the central conduit 166 t and using the flat surface 171 as a seat . next , an o - ring 188 is placed in the groove 108 of the collar / seal ring assembly 136 , and the collar / seal ring assembly is located over the spring . the assembly 136 is pushed against the pressure of the spring 186 so that the top portion of the central conduit 166 t enters the underside of the assembly 136 and pushing is continued until the bottom skirt portion ( b in fig3 ) of the assembly 136 contacts the surface 171 , which simultaneously engages the o - ring 168 in a sealing contact with the smooth bore 312 in fig3 . once the bottom portion b has contacted the surface 171 , the hole 160 in the end of the stem of the valve center is then threaded over the nut ( retaining fastener 176 , fig2 ) securely , so that subsequent releasing of the assembly 136 causes the beveled edge 132 to contact the o - ring 162 on the valve center 154 in a sealing arrangement . the female adapter cover 144 is then slid over the assembly 136 and fastened into position using conventional fasteners threaded through the holes 182 ( fig2 ) and into the threaded holes 52 ( fig2 ). fig4 is a bottom view of the assembled female adapter 701 showing the respective positions of the flange 180 , bolt holes 182 , retaining fastener 176 , fastener boss supports 178 , valve center 154 , central conduit 166 , vapor tube 172 , and the outlet portion 187 of the vapor tube 172 . fig4 is a top view of the assembled female adapter 701 showing the respective positions of its various elements including the top surface 146 , flat top surface 118 , o - ring 130 , flat top 156 , gap 142 , and flat top surface 106 . fig4 shows a perspective view of the inside top portion of the assembled female adapter 701 showing the respective positions of its various elements including the flat top surface 118 , o - ring 130 , flat top 156 , top surface 146 , flat top surface 106 , and gap 142 . fig4 shows a perspective view of the inside top portion of the assembled female adapter 701 in which the surface 118 has been pressed downward , against the force of spring 186 ( fig2 ) showing the respective positions of its various elements including the flat top surface 118 , o - ring 130 , flat top 156 , top surface 146 , flat top surface 106 , gap 142 , and opening o which has been caused to exist by virtue of the collar / seal ring assembly having been depressed against the force of spring 186 ( fig2 ). the construction so described for the female adapter ( or remote portion of a fuel transfer coupling according to the invention ) operates as follows . a force is applied to the surface 118 of the collar / seal ring assembly , against the pressure of the spring 186 this causes the collar / seal ring assembly 136 to be moved inside the smooth bore 196 of the female adapter cover 144 , to open up an opening o through which a fuel may flow by virtue of the beveled surface 132 having moved away from the o - ring seal 162 of the valve center 154 . the collar / seal ring assembly continues its travel downwards opening up the opening o larger and larger until the bottom portion b of the assembly 136 contacts the raised surface 171 . at this point , further pressure on surface 118 causes the seal ring 116 to continue moving downwards , against the pressure of springs 140 , which opens up the gap 142 by virtue of the o - ring seal 122 no longer being in contact with beveled edge 114 . the opening of the gap 142 opens fluid communication between the outlet portion 187 of the vapor tube 172 and the gap 142 , through the holes 174 and shrouding enclosure 170 . reference is now made back to the male adapter 700 . when the male adapter 700 is engaged inside the female adapter cover and the two are pressed together by an applied force , a series of events heretofore unknown in the art occurs . the o - ring 130 on the female adapter 701 contacts the flat top surface 48 of the internal housing 18 . the applied force causes the internal housing 18 to be pressed into the adapter 700 , thus opening the gap 7 , which provides a fluid communication path between the outlet portion 35 of the vapor tube 20 and the gap 7 . continued applied force causes the assembly 136 to be pushed into the smooth bore 196 of the female adapter cover 144 , thus creating an opening o through which a liquid fuel may flow as was shown in fig4 . continued applied force opens the gap 142 by virtue of the assembly 136 bottoming out on the flat surface 171 , as described above , thus providing a fluid communication path between the outlet portion 187 of the vapor tube 172 and the gap 142 . under such an arrangement , the gap 7 of the male adapter 700 and the gap 142 of the female adapter 701 are in fluid contact , which also means that the outlet portion 35 of the vapor tube 20 and the outlet portion 187 of the vapor tube 172 are now in fluid communication with one another . during the course of the applied force , and more or less simultaneously with the afore said events , the flat top 156 of the valve center 154 pushes on the flat top surface 70 of the poppet 10 thus opening space s as described for fig1 , thus enabling fluid contact between the space s on the adapter 700 and the opening o ( fig4 ) of the adapter 701 . establishment of a fluid connection between the opening of space s and the opening o means that there is now a fluid connection between the bottom of the central conduit 166 b and the central bore 34 of the male adapter base 4 . thus , insertion of the outer surface of the male adapter cover 2 of the finished assembly 700 into the bore of the female adapter cover 144 of the finished assembly 701 simultaneously causes a fluid connection to occur between the vapor tubes of each of the coupling counterparts and a fluid connection to occur between the central bore 34 of the male adapter base and the bottom of the central conduit 166 b . according to a preferred form of the invention , the central bore 34 ( fig2 ) of the assembly 700 is connected by conventional means such as a hose to the inlet pipe through which a fuel tank is normally filled , and the outlet portion 35 of the vapor tube 20 is connected by conventional means such as a hose to the headspace above the fuel in a fuel tank , and the assembly 700 is placed in a location at which the orifice through which gasoline is normally added to a vehicle &# 39 ; s gas tank is located . the adapter assembly 701 is fitted to the bottom of a portable fuel reservoir ( or the outlet of a pump ). the outlet portion 187 of the vapor tube 172 is connected by conventional means such as a hose to the headspace above the fuel in the fuel reservoir from where the fuel to be delivered to the vehicle is stored . the central conduit 166 b is connected by conventional means such as a hose to the bottom of the portable reservoir , to be in contact with a liquid fuel . using such provisions , when it is deemed desirable to fill gasoline to the vehicle , insertion of the end of the assembly 700 into the open end of the assembly 701 causes the above - described series of events to occur , thus effectively simultaneously , i . e ., within about less than 1 second , and permits fueling of a vehicle to occur with no loss of vapor to the atmosphere . also , since the volume of fuel delivered from the storage tank to the fuel tank on the vehicle is simultaneously compensated for by an equal exchange of headspace volume as between the two fuel storage vessels , no inhibition of flow is observed . owing also to the nature of the coupling , losses of fuel due to spillage are kept to an absolute minimum , thus reducing fire hazards associated with gasoline spills and effectively eliminating health hazards to persons in the area by virtue of their not breathing volatile materials such as alkyl lead compounds since no spillages occur . these events are depicted in cross - section in fig4 a - 46f . another way of viewing the events associated with the connection sequence may be broken down in the following steps : 1 . o - ring , 148 , engages with adapter cover , 2 . sealing inner portion of coupler and adapter from outside . 2 . o - ring , 130 , of 136 engages with face , 48 , of internal housing , 18 . sealing inner fluid conduit , 34 , from vent cavity , 7 . 3 . assy , 136 , pushes internal housing , 18 , and poppet , 10 , back until face , 51 , contacts face 40 of body , 4 . this opens to vent cavity , 7 . 4 . face , 156 , of poppet , 158 , engages with face , 70 , of poppet , 10 . 5 . poppet , 156 , pushes poppet , 10 , open allowing fluid / fuel to flow from 166 b to cavity 34 . 6 . assy , 136 , is pushed back until face , 201 , of 102 contacts face , 171 , of body , 164 . 7 . housing , 18 , with face , 48 , in contact with o - ring , 130 , pushes inner housing , 116 , back opening vent cavity , 142 ?, to vent port , 172 . 8 . coupler assy . continues forward until face , 146 , of adapter cover , 144 , contacts the heads of screws , 22 , of male adapter . coupler is now fully engaged and all ports are fully open . the occurrences of the above events are described according to one preferred form of the invention . however , it will occur to one of ordinary skill in the art after reading this specification that the events are controlled by the strengths of the various springs 8 , 12 , 186 , and 140 selected . according to a preferred form of the invention , the event which is the last to occur is the opening of the gap 142 in the assembly 136 . the vent disc 14 on the assembly 700 is spring - loaded , as previously described herein . the purpose of this is to enable ambient air to enter the fuel tank after a quantity of fuel has been removed from the fuel tank by the action of the fuel pump . when the fuel pump removes fuel from the fuel tank during its normal operation , a vacuum will be developed within the fuel tank because of the volume of fuel removed . when the coupling of the present invention is utilized , once the vacuum inside the fuel tank reaches a sufficient level that the spring 12 can no longer hold the vent disc 14 in its seated position , the vent disc is drawn away from it seat , and enables ambient air to enter the tank to compensate for the loss of fuel or other cause of vacuum in the tank , such as a sudden temperature decrease . in addition , the vent disc 14 includes a hole 15 in its surface , which acts as a vent to vent out any pressure which may build up in the tank , owing to increases in temperature or other causes . fig4 shows a perspective view of a fuel containment system comprising a fuel reservoir 609 having an inlet pipe 611 and containing a liquid fuel and a headspace 613 , and further comprising the coupling 700 , wherein the vapor tube 20 is in effective fluid contact with the headspace 613 above the fuel in said fuel reservoir by means of a tube 615 , and wherein the first end portion 34 of the central bore portion is in effective fluid contact with the inlet pipe 611 . fig4 shows a perspective view of a fuel containment vessel 617 comprising an outlet 625 and containing a liquid fuel 621 and a headspace 619 , and further comprising the coupling 701 , wherein the vapor tube 172 is in effective fluid contact with the headspace 619 above the fuel 621 in said fuel containment vessel by means of a tubing 623 , and wherein said central conduit portion is in effective fluid contact with said outlet 625 . there is also shown a valve means 627 disposed between said outlet 625 and said central conduit portion . consideration must be given to the fact that although this invention has been described and disclosed in relation to certain preferred embodiments , obvious equivalent modifications and alterations thereof will become apparent to one of ordinary skill in this art upon reading and understanding this specification and the claims appended hereto . the present invention further includes all possible combinations of the features recited in any one of the various claims appended hereto with the features recited in any one or more of each of the remaining claims . accordingly , the presently disclosed invention is intended to cover all such modifications , alterations , and combinations .