Model DA1 Rev E Pressure Reducing Regulator; 4" Line Size; Stainless Steel Body With Stainless Steel Spring Chamber; SK 316L Stainless Steel Trim, Polyurethane Seat, Fluorosilicone Diaphragm, Fluorosilicone Static Seal, PTFE Cap With Fluorosilicone Energizer And GF-TFE Wiper Dynamic Seal; OPT-30: Mates With ASME 150 Raised Face Flanges; 40-125 PSIG Range Spring; Internal Sensing; OPT-55: Cleaned For Oxygen Service Per Cashco Specification S-1134