Model HP Rev A Pressure Reducing Regulator, PTFE/FKM Gaskets (Opt-45); 1/2" Line Size; Caron Steel Body With Carbon Steel Spring Chamber; S36 Trim: 316 Stainless Steel With PTFE Seat, 302 Stainless Steel Diaphragm; OPT-30: Mates With ASME 300 Raised Face Flanges; 10-40 PSIG Range Spring