Model D Rev D Pressure Reducing Regulator For General Service; 3/8" Line Size; Carbon Steel Body And Spring Chamber; S6 Trim: 316 Stainless Steel With Ethylene Propylene (EPR) Seat And Ethylene Propylene Diene (EPDM) Diaphragm; NPT Threaded End Connections; 2-15 PSI Range Spring; Opt-4: Piston Stabilizer For Gaseous Service; Polyethylene Vented Spring Chamber Plug