Waterway Check Valves have a clear lid with union lock ring and a bright seal flapper for easy inspection and quick access. The Waterway Check Valves have the swing design to be used for both return and intake water. CPVC Hi-Temp plastic body which features deeper sockets than others for better glue joints, and is available in a straight body or 90 degree style. Waterway's new 3" TruSeal Check Valve has a clear lid with union lock ring and bright blue seal flapper for quick access and easy inspection. The spring/swing design can be used for both return and intake water. CPVC Hi-Temp plastic bodies features deeper sockets for better glue joints.