MODEL "CA-1" BACK PRESSURE RELIEF REGULATOR 1/4" ANGLE DESIGN,SIDE INLET,BOTTOM OUTLET; 316L SST BODY & SPRING CHAMBER; S40G TRIM: 303SST METAL SEAT, GYLON DIAPHRAGM, NACE CONSTRUCTION; NPT SCREWED; 100-175 PSIG RANGE SPRING; PER SPQ NUMBER 57279 WITH NO STEEL COMPONENTS TO PREVENT CORROSION; OPT-2: HANDWHEEL; OPT-55: CLEANED FOR OXYGEN SERVICE PER SPEC #S-1134;