The 2-½”-3” Repair Kit is a complete internal rebuild solution for maintaining and restoring the performance of reduced pressure principle assemblies (375 models). Designed for 2-½” and 3” models, this comprehensive kit contains all major components needed to return your backflow preventer to peak operating condition, including check valve parts, relief valve internals, O-rings, seals, springs, and lubricant. This full internal service kit helps maintain consistent water pressure, proper sealing, and compliance with plumbing standards.