Our swing check valves are designed to prevent backflow. The clapper is spring loaded allowing the check valve to be mounted horizontally or vertically. Specifications: 200 PSI rated Opens at 2 PSI Spring Loaded F NPT x F NPT Download Spec SheetTabsPart Finder Size ½”¾”1”1¼”1½”2” Result SKU: SPCV1 Part Table 6 Items Part Size SPCV1SPCV1 1” SPCV1/2SPCV1/2 ½” SPCV125SPCV125 1¼” SPCV15SPCV15 1½” SPCV2SPCV2 2” SPCV3/4SPCV3/4 ¾”