Model "D" Pressure Reducing Regulator,Graphite/Nbr Gaskets; 1" Size; Wcb Body,Cast Iron Spring Chamber; B2 Trim: Brass With Buna-N (Nbr) Seat,Neoprene (Bc) Diaphragm; Opt-30: 150 Lb Raised Face Flanges; 70-150 PSIG Range Spring; Opt-4: Stabilizer (Recommended For Gaseous Service Only); Opt-25: 1/8" Npt Spring Chamber Vent Tap