This Watts repair kit is designed for use with 900 Watts backflow preventers of sizes 3/4", 1", and 1-1/4". The kit contains components necessary for maintenance and repair, including an inlet adaptor gasket, two types of check valve assemblies (each with specific springs and o-rings), two union nut gaskets, a relief valve spring, a stem o-ring, a maintenance tool, and silicone grease. These parts assist in restoring the functionality of the backflow preventer by replacing worn or damaged components.