90001-MZ8-U40 Bolt Flange (6X18) - Overview. The 90001-MZ8-U40 Bolt Flange (6X18) is an essential fastening component designed for Honda marine engine systems. This genuine OEM part plays a critical role in securely mounting components where exact fit and reliability are paramount. Engineered to Honda's precise specifications, it ensures seamless integration with existing parts, maintaining optimal performance and durability.. Key Features. Specifically designed as a flange bolt measuring 6mm by