MODEL "B2", BACK PRESSURE REGULATOR 1/4" SIZE, CV=0.20; BRASS BODY, 6061 AL SPRING CHAMBER; 302 SST W/TEFZEL RING DIAPHRAGM, TFE SEAT, 316L SST W/PCTFE SEAL, PORT CONFIGURATION "A"; FNPT END CONNECTION; 5-500 PSIG RANGE SPRING; NO INLET GAUGE; CLEANED FOR OXYGEN SERVICE PER SPEC #S-1134;