The Thetford 94135 Freshwater Bypass Valve is a 3-way diverter valve designed to be used with Thetford's Nautilus P2 and P1 panels. It allows you to choose the water flow, such as directing freshwater to the system or bypassing the freshwater tank. Used in RVs and campers to help maintain a smooth-flowing and leak-free plumbing system.• Three ports allow different water flow configurations• Specifically designed for use with Nautilus P2 and P1 control panels• Helps prevent leaks and allows manual control over water system Allows you to choose water flow such as freshwater to system or bypassing tank Helps prevent leaks & allows manual control over water system | B&W Thetford 94135 Fresh Water Bypass Valve