90405-ZV4-811 Washer (6Mm) - Overview. The 90405-ZV4-811 Washer (6Mm) is a crucial component in Honda marine engine systems. It serves primarily as a fastener washer, supporting mechanical assemblies by distributing load evenly and providing necessary spacing. This small yet vital part ensures the reliable performance and durability of your marine engine by maintaining secure connections within the system. Designed to precisely match factory specifications, it ensures seamless integration with e