MODEL "DA1" PRESSURE REDUCING REGULATOR (SERIES I) BODY SIZE 1/2",STANDARD DIAPHRAGM CONSTRUCTION; BRONZE BODY & SPRING CHAMBER; 17-4PH SST TRIM, 316L SST CAGE, PA SEAT, BC DIAPHRAGM, NBR STATIC SEAL, O-RING DYNAMIC SEAL; NPT END CONNECTION; 20-80 PSIG RANGE SPRING; INTERNAL SENSING, STANDARD - FLOW TO OPEN DIRECTION; OPT-55: CLEANED FOR OXYGEN SERVICE PER SPEC #S-1134;