Model DA1 Rev E Pressure Reducing Regulator; 1-1/2" Line Size; Stainless Steel Body With Carbon Steel Spring Chamber; MW Monel Trim BUNA-N Seat, BUNA-N Diaphragm, BUNA-N Static Seal, BUNA-N O-Ring Dynamic Seal; OPT-30: Mates With ASME 300 Raised Face Flanges; 40-175 PSIG Range Spring; Internal Sensing; OPT-25: 1/4" NPT Spring Chamber Vent Tap