90302-ZV5-003 Hex (20mm) Nut - Overview. The 90302-ZV5-003 Hex (20mm) Nut is an essential component in Honda marine engine systems. This hexagonal nut plays a critical role in mechanical fastening, providing secure connections within the engine rigging and accessory systems. Designed to meet stringent Honda marine specifications, it ensures seamless integration with existing parts, maintaining optimal performance and durability.. Key Features. Genuine Honda OEM Hexagonal Nut sized at 20mm design