Most check valves are constructed of non-transparent materials. Therefore, you are unable to visually see flow through the valve. Likewise, standard check valves may produce a slamming sound when the water flow reverses in the discharge pipe after a pump stops. This is commonly referred to as water hammer. If you'd like to see flow and reduce water hammer, the Clear Quiet Check Valve is a perfect solution. Like any good check valve, it also protects your pump by providing reliable backflow prevention.This quiet check valve offers the features provided in a standard check value with the addition of a hinged, spring-loaded flapper. This mechanism makes the flapper fully close against the fluid flow as the pump shuts down. Rapid closure against pressure before any flow reversal can occur eliminates the noise caused by hydraulic shock.Designed for full flow with a clog-resistant design, it can be installed in a vertical or horizontal orientation. The solvent-weld ends with unions on the quiet check valve make it easy to install. Additionally, the union on either end simplifies pump removal when it becomes necessary.