Model "DA8" Differential Back Pressure Regulator (Series VIII)-PDBPV; Body Size 2",Standard Diaphragm Construction; Sales Kit A; Cf3m Body,316l SST Spring Chamber,1/8" Petcock Vent; 316l SST Trim, V-Tfe Seat, Be-Cu Diaphragm,;SST/Tfe U-Cup Static Seal, SST/Tfe U-Cup Dynamic Seal; 15-50 PSId Range Spring;