In alternate embodiments, the pressure regulators are pressure regulating screws, valves, dispensing conduits having various cross sectional areas, and {HEAD ~ reservoir conduits} having {TAIL ~ various cross sectional areas} 
having
In alternate embodiments , the pressure regulators are pressure regulating screws , valves , dispensing conduits having various cross sectional areas , and { HEAD ~ reservoir conduits } having { TAIL ~ various cross sectional areas }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL