Model "DA4" Pressure Loaded Reducing Valve (Series IV)-PLPRV; Body Size 2",Standard Diaphragm Construction; Sales Kit A; Bronze Body & Loading Chamber; 17-4ph SST/Monel Plug,Piston Guide Bearing,Cage;Fluorosilicone(Fk);Diaphragm,Polyall Seat; Fluorosilicone(Fk) Static Seals,Tfe Cap Seal W/Fluorosilicone(Fk);Energizer Dynamic Seal,Gf-Tfe Wiper; Opt-55: Special Cleaning & Packaging For Oxygen Service Per Spec#;S-1134