WaveEater Towing water supply valve for all Yamaha 4 stroke WaveRunners Valves off cooling water hose to keep engine from flooding with water while being towed behind a boat A Must Have if towing your PWC in the water dont take a chance on flooding your engine without a Tow Valve Specifically sized for the 4 stroke yamaha engine used in the FX140 and all versions of the Yamaha 4 stroke pwc engine