Flush Pro Valve - 5/8' Finally! Fresh flushing of your inboard is as simple as connecting a garden hose. Features: * Polymer * Stainless Steel Spring * Flush your boat engine safely and easily * Transparent body allows for visual inspection of water flow * Durable check valve system activated by water pressure from a garden hose * Check valve automatically shuts off hull intake when water pressure is applied * Adapter supplied with Flush Pro make winterizing your boat easy * Can be used with on board generators * Available for Standard 5/8' Hose Sizes