In-Line Non-return ValveNon-return valves help priming and prevent backflow of water into the bilge. WARNING: This product can expose you to chemicals including NICKEL (METALLIC) which is known to the State of California to cause cancer. For more information go to P65Warnings.ca.gov. Specifications: Inlet Size: 3/4" Outlet Size: 3/4" Type: Misc Box Dimensions: 2"H x 4"W x 6"L WT: 0.2 lbs UPC: 671880551397 Quick Guide (pdf)