Abstract: An adapter for connection with the access valve fitting of a closed refrigeration system which includes a screw threaded coupling engaged with the externally threaded nipple on the refrigeration system with the adapter including a screw threaded adjustable abutment member in a normally open passage for automatically opening the normally closed "Schrader" valve with the adapter itself including a duplicate "Schrader" valve oriented in perpendicular relation to the axis of the existing "Schrader" valve and perpendicular to the longitudinal axis of the adapter itself with the adapter also including threaded fittings enabling connection with a pressure gauge, hose, closure cap, or the like.