Check valve, also known as non-return valve, check valve or check valve to prevent the function of the line of medium directional flow without reflux; imports of stainless steel check valve is made ??of stainless steel (304,316,316 L) the most material of the valve body and the valve plate check valve, opening and closing pieces by medium flow and strength to turn itself on or off, to prevent the media back valve. Is divided into stainless steel swing check valves, stainless steel lift check valve, foot valve, stainless steel check valve, butterfly check valve.