Model "CA-2" Back Pressure Relief Regulator; 1/2" Angle Design,Side Inlet,Bottom Outlet; 316l SST Body & Spring Chamber; S2 Trim: 303SST Metal Seat,302SST Diaphragm; Npt Screwed; 80-150 PSIG Range Spring; Cryogenic Construction (Opt-36), Includes Opt-55: Cleaning For Oxygen Service Per Spec #S-1134