The Complete Pressure Vessel Repair Kit is compatible with the 3/4” Model 375 and 375XL Reduced Pressure Principle Backflow Preventer. Repair Kit components include one Pressure Vessel, two Ball Valve O-Rings, one Sleeve, two Sleeve/#1 Seat O-Rings, four Sleeve Bolts, three Test Cocks, one Seat #1, one Spring #1, one Spring Retainer #1, two Seat Bolts, two Seal Retainers, two Seal Washers, two Poppets, one #2 Seat O-Ring, one Seat #2, two Spring #2, one Spring Retainer #2, one Relief Valve Seal Washer, one Relief Valve Seal Retainer, one Relief Valve Bolt, one Relief Valve O-Ring, one Relief Valve Nut, two Sensing Port O-Rings, one Relief Valve Body, one Relief Valve Seat, one Relief Valve Spring Guide, one Relief Valve Spring, one Diaphragm, one Relief Valve Plunger, one Plunger O-Ring, one Relief Valve Cover O-Ring, one Relief Valve Cover, one Cover Bolt, one #1 Spacer, and three Test Cock Cap Plugs. The accessories within the kit allow you to speed up repairs, while lowering maintenance costs and extending the product life. The Zurn Wilkins portfolio offers long-lasting protection from backsiphonage and backpressure of contaminated water into the potable water supply.