Model "DA2" Differential Pressure Reducing Regulator (Series II)-PDRV; Body Size 1/2",Standard Diaphragm Construction; Sales Kit A; Cf3m Body,316l SST Spring Chamber,1/8" Petcock Vent; 17-4ph SST Trim, 316l SST Cage, Epr Seat, Epr Diaphragm,;Epr Static Seal, O-Ring Dynamic Seal;