American STANDARD CHECK VALVE IS DESIGNED AND manufactured according to American standard completely, with beautiful and advanced structure. American standard check valve refers to relying on the flow of the medium itself and automatically open and close the disc, used to prevent the backflow of the medium valve, also known as check valve, check valve, counterflow valve, its main role is to prevent the backflow of the medium, prevent the pump and the drive motor reverse, and the release of the container medium.