Model "DA4" Pressure Loaded Reducing Regulator (Series IV)-PLPRV; Body Size 1/2",Opt-81: Full Diaphragm Support Construction; Sales Kit A; Cf3m Body,316l SST Loading Chamber; 17-4ph SST Trim, 316l SST Cage, Pa Seat, Epr Diahpragm;Epr Static Seal, Tfe Cap W/Epr Energizer Dynamic Seal, Gftfe Wiper; Opt-56: Special Cleaning Per Spec #S-1542