Inline Non-Return ValveCOMPLETE YOUR BILGE SYSTEM Fit Whale high quality pumps and accessories to ensure long term reliability throughout your bilge system. Optimise your bilge pump&';s performance by preventing back flow.WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings.ca.gov.