Wafer disc check valves are suited for weight- and space-limited applications in chemical processing, HVAC, water distribution, and various other industries. Media flowing backward through the system moves the disc back into the seat to stop media and contaminants from entering the source. Flowing media pushes the disc away from the valve seat, creating a flow path for media. Media flowing backward through the system moves the disc back into the seat to stop media and contaminants from entering the source.