The GAIRUI Non-slam nozzle check valves is a streamlined venture port design so as to reduce pressure loss. This series valve disc is the only moving part to minimize internal wear and compressed disc spring initiates valve closure as flow slows down and provides quick reaction on flow velocity change. It can be used in a wide range of critical and demanding services applications such as fast reversing reciprocating compressor system or installations where the check valve must be placed in close proximity to the pump inlet or outlet.