Model 1000LP Rev A Pressure Reducing Regulator, PTFE/Al-Silicate Gaskets; 1" Line Size, Gaseous Jet; Carbon Steel Body With Carbon Steel Spring Chamber; S3N Trim: 316 Stainless Steel With BUNA-N (NBR) Seat, Neoprene (BC) Diaphragm; OPT-30: Mates With ASME 150 Raised Face Flanges; 4-15 PSIG Range Spring; OPT-17: Piston Spring; OPT-25: 1/4" NPT Spring Chamber Vent Tap