Check Valves Cla-Val’s sturdy and reliable check valves provide non-slam closure, have a low head loss and close drip-tight. 81-01 & 681-01 Check Valve 81-02 & 681-02 Check Valve 81-18 Check Valve 81-12 Check Valve 580 Series Silent Wafer Check Valve 581 Series Silent Globe Check Valve 582 Series Two-Door Wafer Check Valve 583 Series Foot Valve 584 Series Flex-Check Valve 585 Series Swing Check Valve 586 Series Pivoting Disc Check Valve 587 Series Surge Blocker 501A Series Wafer Swing Check Valve Downloadable Files Check Valve Product Warranty RF-DB Duckbill Check Valve Brochure Check Valve Brochure