Model "DA1" Pressure Reducing Regulator (Series I); Body Size 4",Standard Diaphragm Construction; Sales Kit A; Cf3m Body,Cast Iron Spring Chamber; 316l SST Plug/Cage/Piston Guide Bearing,Buna-N(Nbr) Diaphragm,Polyall;Seat; Buna-N(Nbr) Static Seals,Buna-N(Nbr) O-Ring Dynamic Seal;