A Check Valve, Non-Return Valve or One-way Valve is a Valve that normally allows fluid(liquid or gas) to flow through it in only one direction. Stainless Steel Check Valve are two-port valves, meaning they have two openings in the body, one for fluid to enter and the other for fluid to leave. There are various types of check valves used in a wide application. 

Such as Swing Check Valve(Threaded & Flanged), Spring Vertical Check Valve(Threaded & Flanged), H71 Wafer Disco Check Valve, H74 Single Door Check Valve, Y-type Threaded Check Valve, 3 Piece Threaded Check Valve and so on.