Hh44x micro resistance slow closing check valve is used in water supply and drainage pipeline. It is installed at the outlet of water pump to prevent medium backflow and eliminate destructive water hammer. It can effectively reduce the closing water hammer pressure of valve and ensure the safe operation of pipe network. It has the characteristics of light valve disc, large opening, remarkable power saving effect, small fluid resistance, novel design of water hammer elimination mechanism, stable and reliable sealing performance, wear resistance, long service life, stable operation, no vibration and no noise.