90203-ZV4-811 Nut-Washer (6mm) - Overview. The 90203-ZV4-811 Nut-Washer (6mm) is a precision-engineered fastener designed specifically for Honda marine engine systems. It plays a crucial role in securely fastening components while evenly distributing pressure to prevent damage and maintain system integrity. Manufactured as a genuine OEM part, the nut-washer integrates seamlessly with existing hardware, providing consistent reliability and durability under marine conditions.. Key Features. 6mm Nu