With body, disc, and stopper assembly machined from solid, chemically resistant PVC plate stock, 3 in. PVC wafer check valve operates at 150 psi max and installs on discharge side of pumps to prevent back-flow flooding. Unit installs by slip-fitting between 2 mating flanges, automatically centers on mating flanges, and conforms to ISO 5752 face-to-face dimensions. Standard versions comes with EPDM seals and no spring, and options include FKM seals and ETFE-coated stainless steel spring.