Disc Check Valves feature a wafer type, compact and rugged Cast Carbon Steel or Stainless Steel design and are suitable for any process liquid, air, gas, steam etc. The Single Disc Check Valve (Wafer Type Disc Check Valve) consists of four main components: the body, a disc, a star guide and a spring. The Disc check valves are opened by the pressure of fluid and closed through compression spring as soon as flow stops thus preventing reverse flow.