Model D Rev D Pressure Reducing Regulator For General Service; 1/2" Line Size; Stainless Steel Body And Spring Chamber; S2 Trim: 416 Stainless Steel Metal Seat And 302 Stainless Steel Diaphragm; NPT Threaded End Connections; 2-15 PSI Range Spring; Opt-25S: Stainless Steel Vented Spring Chamber Plug