90161-ZW4-000 Flange (10X55) Bolt - Overview. The 90161-ZW4-000 Flange (10X55) Bolt is a critical fastening component designed for Honda marine engine systems. This bolt, with a 10mm diameter and 55mm length, serves as an essential mounting element in the marine engine assembly, securing parts firmly and contributing to the overall structural integrity. Engineered to meet precise OEM specifications, it ensures seamless integration with existing parts, maintaining optimal performance and durabili