What This Part Is Used For The Hayward GMX400F O-Ring provides a sealing surface for compatible Hayward filter or valve assemblies. It prevents water leaks at connection points. Why This Part Matters A worn or flattened O-ring can cause air leaks, water seepage, or pressure loss. Replacing it restores proper sealing and system integrity. Small sealing components play a major role in overall equipment performance. Key Features and Specifications Genuine Hayward O-ring Manufacturer part number: GMX400F Sealing component For compatible Hayward assemblies Helps prevent leaks and air intrusion Installation and Fitment Guidance Clean sealing surfaces before installation and lubricate with appropriate pool lubricant. Confirm by manufacturer part number before ordering. About the Hayward Brand Hayward is known for precision-molded components in pool equipment. Their sealing systems are engineered for reliable performance. Genuine O-rings maintain factory fit. Pool technicians depend on Hayward for dependable replacement parts. Common Service Context Frequently replaced during filter service, multiport valve maintenance, or when addressing minor leaks.