90201-ZY6-000 Nut (6mm) - Overview. The 90201-ZY6-000 Nut (6mm) is a vital fastening component used in the Honda marine engine systems, primarily within rigging and accessory assemblies. This flange cap nut is engineered to securely mount various parts, ensuring the mechanical stability and operational integrity of your marine engine. Designed as a genuine OEM part, it plays a key role in maintaining system reliability and ease of maintenance by matching factory exact dimensions and tolerances,