Model "DA5" Back Pressure Regulator (Series V)-BPV; Body Size 3",Standard Diaphragm Construction; Cf3m Body,316l SST Spring Chamber; 17-4ph SST Trim, 316l SST Cage, Fkm Seat, Fkm Diaphragm;Fkm Static Seal, SST/Tfe U-Cup Dynamic Seal; PN16 Raised Face Din Flanges; 40-125 PSIG Range Spring; Large Internal Sensing, Reverse - Flow To Open Direction; Opt-56: Special Cleaning Per Spec #S-1542