the invention disclosed herein comprises a device 10 that is permanently and fixedly attached by a member of the household to the sock 15 as shown in fig1 . the device 10 is typically provided in pairs 12 , wherein each device 10 possesses identical indicia 20 for identification purposes . the devices comprising pairs 12 are attached to mating pairs of socks 17 so that the socks belonging to individuals in the same household or communal unit can be sorted according to ownership , color and original match by matching the indicia 20 provided on the devices 10 comprising pair 12 . fig2 shows the two principal elements of the device 10 comprising the present invention . the device 10 generally comprises a first clamping element 30 and a second clamping element 35 . the first clamping element 30 consists of a base 40 having a first surface 42 and a second surface 44 . the first surface 42 has indicia 20 stamped thereupon . the second surface 44 has a solid post 50 extending therefrom and terminating into a free end 55 . the solid post 50 has a cross section 52 and a lateral exterior surface 51 on which fastening means 53 are provided . the cross section 52 , which may be of any arbitrary selected shape , is preferably either circular 52 as in fig2 elliptical or oval 54 as in fig3 ( a ), square 56 as in fig3 ( b ), or rectangular 58 as in fig3 ( c ). the base 40 is preferably an ovate or round disc with flat first 42 and second 44 surfaces that are also parallel to each other as seen in fig2 . the fastening means 53 on the exterior lateral surface 51 preferably comprise grooves 59 or ridges 57 provided on the lateral surface 51 as shown in fig4 ( a ) and 4 ( b ) respectively . the grooves 59 or ridges 57 , which are transverse to the length of the solid post 50 and enclose an area that is coaxially disposed with cross section 52 , are provided along the length of the solid post 50 . the grooves 59 and ridges 57 are preferably spaced equally with respect to each other along the length of solid post 50 and are preferably also angled towards the base 40 of the first clamping element 30 . in use , the second clamping element 35 is designed for permanently and fixedly attaching to first clamping element 30 . the second clamping element 35 has a base 60 having a first surface 62 and a second surface 64 . the first surface is defined by an outer perimeter 61 and an inner perimeter 63 . the second surface 64 has an internally hollow post 70 extending therefrom that terminates into a solid pointed free end 75 . the lateral interior surface 65 of the hollow post 70 extends from perimeter 63 to solid pointed end 75 . the cross section 66 defined by the interior surface 65 of the internally hollow post 70 is coincident and coaxial with the cross sectional area enclosed by the inner perimeter 63 . the hollow post 70 has an exterior surface 67 defining the second clamping element wall thickness 71 . as shown in fig5 the interior surface 65 encloses a locking channel 69 within which coupling means 80 are provided that fasten securely to fastening means 53 of first clamping element 30 when in use . means 53 comprise grooves 59 or ridges 57 . for accomplishing the purposes of the invention , the cross sections 52 of solid post 50 and 66 of internally hollow post 70 are similar to and compatible with each other , so that the solid post 50 may be received within the locking channel 69 from the normally closed pointed end of the second clamping element after exposing channel 69 by clipping away the solid end 75 and inserting solid post 50 into the thusly exposed channel 69 . the internally hollow post is preferably an internally hollow cylinder with a circular cross section compatible with the solid post 50 which is also preferably cylindrical having a circular cross section 52 . while the solid pointed free end 75 , which caps and seals the locking channel 69 of internally hollow post 70 may be of arbitrary geometry , it is preferably a solid cone with a sharp pointed vertex 77 and a circular base 79 coaxial and coincident with the preferred circular cross section of the exterior surface 67 . the base 60 of the second clamping element 35 is preferably an ovate or round disc , whose first surface 62 and second surface 64 are preferably flat and parallel to each other . the coupling means 80 of the internally hollow post 70 , shown in fig5 preferably comprise grooves 82 or ridges 84 on interior surface 65 that are angled towards the base 60 , and are respectively compatible with and mated to the grooves 59 or ridges 57 of solid post 50 . the first 30 and second 35 clamping elements , which may be made from a variety of materials , are preferably made of engineering thermoplastic materials using high speed injection molding processes known in the art . while the purposes of the invention may be accomplished with both clamping elements 30 and 35 made from like material such as nylon , the first clamping element 30 is preferably made of a compliant thermoplastic and the second clamping element 35 of a more rigid thermoplastic . alternatively , the first clamping element 30 could be made of a rigid plastic and the second clamping element 35 of a more compliant plastic . while indicia 20 used for identifying mating sock pairs 17 to which identical devices are permanently and fixedly attached in pairs may be provided on either clamping element , they are preferably provided on the first surface 42 of the first clamping element 30 . the indicia scheme claimed and practiced according to the present invention provides identification with respect to sock ownership , sock color , and sock mating to the original matched pair . ownership is determined with a symbol , such as a golf club or a tree ; the color is identified by an abbreviated descriptor such as blk for the color black ; and mating to the original matched pair , thereby accommodating subtle variations in color scheme , is achieved by using a number , such as 01 or 99 . fig6 shows an example of indicia using these features , which are provided in identical pairs for practicing the present invention . because indicia are always provided on the first clamping element , which the user may have appear on either the inside or the outside of the sock , information is readily obtained as to whether the sock has been worn with the right side exposed . the device is preferably attached with the first clamping element 30 bearing indicia 20 appearing on the inside of the sock so as to provide a smooth surface in contact with the skin of the wearer . the two clamping elements 30 and 35 are preferably made so that the first clamping element 30 , bearing indicia 20 , is made in basic colors black , brown , red , blue and white , or in transparent plastic to closely resemble the color of the sock indicated in indicia 20 . distinctive indicia 20 , easily identifiable in a minimum of light and presented in a vivid contrasting color compared to its base , is obtained on the surface 42 of first clamping element 30 in the as - molded condition or may be produced by processes such as hot stamping of the molded part 30 . while the second clamping element 35 may also be made in colors matching those of the first clamping element , it is preferably made from transparent plastic , which offers the greatest degree of non - noticeability when the device is worn with the surface 62 of second clamping element 35 appearing on the outside of the sock . in the preferred embodiment , the present invention is practiced according to the steps shown in fig7 . the free pointed end 75 of the internally hollow post 70 of the second clamping element 35 , which is made of rigid plastic , is made to contact the exterior surface 120 of the sock wall 19 and the post 70 forced to penetrate the sock wall 19 by manually pushing on the first surface 62 of clamping element 35 as one would a thumbtack . the clamping element 35 comes to rest as its second surface 64 contacts the exterior surface 120 of the sock wall as shown in fig7 ( a ). the length of the internally hollow post 70 protruding beyond the interior surface 122 of the sock wall 19 is clipped close to the interior surface 122 of the sock wall 19 by the installer of the device with commonly available tools in all households such clippers or scissors . this removes the free end 75 and a portion of the internally hollow post 70 thereby exposing the locking channel 69 as in fig7 ( b ). the free end 55 of the solid post 50 of the first clamping element 30 is then inserted into the exposed channel 69 as in fig7 ( c ). the first surface 62 of second clamping element 35 is supported so as to maintain intimate contact with the sock wall exterior surface 120 as the solid post 50 of the first clamping element 30 is pushed by applying finger pressure on its first surface 42 into the locking channel 69 at the clipped end of the second clamping element 35 as one would a thumbtack . the first clamping element 30 comes to rest when its second surface 44 contacts the interior surface 122 of the sock wall 19 . the fastening means comprising the grooves 82 or ridges 84 of the second clamping element then permanently and fixedly attach to the coupling means comprising the grooves 59 and ridges 57 of the first clamping element to permanently and firmly fasten the device elements 30 and 35 to each other , trapping between them a portion of the sock wall 19 . as shown in fig7 ( d ), the length of the solid post 50 protruding and extending beyond the first surface 62 of the second clamping element 35 is clipped by the installer of the device to present two smooth surfaces on either side of the sock wall , one of which , preferably the first surface 42 of first clamping element 30 , contacts the user &# 39 ; s skin when the sock is worn . although attachment of the two clamping elements can be achieved by providing a ridge in one element and a corresponding groove in the other , stronger and more permanent fastening is achieved by preferably providing for ridges on both clamping elements that are angled towards their respective bases . thus , as the solid post of the first clamping element is inserted into the locking channel of the second clamping element , their respective ridges deform as they interfere with each other ( the more compliant ridges deforming more than the rigid ones ). this deformation is released as soon as the interference is overcome . because of the opposed angled geometry of the ridges , the two clamping elements 30 and 35 are permanently and fixedly locked into place . alternate fastening means may be similarly provided for rigidly securing the two clamping elements and are within the scope of the claimed invention . because a single point fixed contact in the above embodiment of the present invention allows the device to freely rotate while in use , a second embodiment of the preferred invention shown in fig8 uses a plurality of solid posts 130 on the base 40 of the first clamping element 30 and an equal corresponding plurality of mating internally hollow posts 140 on the base 60 of the second clamping element 35 . some or all of the mating pairs of solid posts 130 and internally hollow posts 140 are provided with similar fastening means 132 and 142 as herein described in fig4 and 5 on their respective external 134 and internal 144 surfaces . in the second embodiment of the preferred invention , the plurality of each of the solid 130 and hollow 140 posts is preferably two . the solid posts 130 and the hollow posts 140 are positioned respectively on the second surfaces 44 and 64 of bases 40 and 60 respectively , according to the same identical geometric pattern and spacing so that all the solid posts 130 are simultaneously inserted into their mating locking channels 146 of posts 140 for permanent non - rotational attachment of the device to the sock . in yet a third embodiment of the preferred invention , for ease of insertion , the external surfaces 134 of the solid posts 130 of the first clamping element 30 may be tapered such that their areas of cross section 52 progressively decrease towards their free ends 55 . see fig9 ( a ). similarly , as in fig9 ( b ), tapered external surfaces 148 may also be provided for the internally hollow posts 140 of the second clamping element 35 such that they also progressively narrow from their base 60 to their free ends 75 . other embodiments of the claimed invention , which would be apparent to those skilled in the art , are within its scope . the device comprising the present invention is to be limited only by the claims herein presented , and not by what has been particularly described in this specification .