90305-ZW4-000 Flange (10mm) Nut - Overview. The 90305-ZW4-000 Flange (10mm) Nut is a precision-engineered fastening component designed specifically for Honda marine engine systems. This 10mm flange nut plays a critical role in securing various parts of the engine or rigging accessories, ensuring reliable operation and maintaining the structural integrity of the marine equipment. Made to meet exact factory specifications and tolerances, it ensures seamless integration with existing parts, maintai