90472-723-000 Washer, Plain (12mm) - Overview. The 90472-723-000 Washer, Plain (12mm) is a critical hardware component designed for Honda marine engine systems. This washer plays a fundamental role in the assembly and operational reliability of marine equipment by distributing pressure evenly and securing connected components. It ensures seamless integration with existing parts, maintaining optimal performance and durability.. Key Features. Plain washer with a precise 12mm diameter tailored for