Model D Rev D Pressure Reducing Regulator For General Service; 3/8" Line Size; Ductile Iron Body And Spring Chamber; B1 Trim: Brass Metal Seat With 302 Stainless Steel Diaphragm; NPT Threaded End Connections; 2-15 PSI Range Spring; Opt-4: Piston Stabilizer For Gaseous Service; Polyethylene Vented Spring Chamber Plug