Model CA-2 Rev A Back Pressure Regulator; 1/2" Line Size, Globe Design, Side Inlet-Side Outlet; Sales Kit A; Bronze Body With Bronze Spring Chamber; M7 Trim: Monel Metal Seat, Phosphor Bronze Diaphragm; 250-400 PSIG Range Spring; OPT-5: Cryogenic Construction, OPT-55: Cleaned For Oxygen Service Per Cashco Specification S-1134