90204-ZY1-003 Lock (6MM) Nut - Overview. The 90204-ZY1-003 Lock (6MM) Nut is a genuine OEM component designed to support the rigging and fastening systems within Honda marine engine systems. Its primary role is to provide a secure and reliable fastening solution, ensuring vital parts remain firmly in place during operation. Manufactured to meet the precise factory specifications, this lock nut guarantees seamless integration with existing hardware, maintaining optimal performance and long-lastin