MODEL "2171" BACK PRESSURE RELIEF REGULATOR, TFE GASKET/O-RING 1/4" SIZE, ANGLE DESIGN (TWO SIDE INLETS - BOTTOM OUTLET); 316L SST BODY, BRONZE SPRING CHAMBER; S3 TRIM: 316L SST WITH TFE SEAT,NEOPRENE (BC) DIAPHRAGM; NPT SCREWED; 70-140 PSIG RANGE SPRING; OPT-2: HANDWHEEL;