40201-ZY3-020ZD Case *NH565* - Overview. The 40201-ZY3-020ZD Case *NH565* is an essential housing component within Honda marine engine systems. This extension case plays a critical role in protecting internal engine parts and contributing to the overall structural integrity of the engine assembly. Designed specifically for Honda marine engines, it ensures seamless integration with existing parts, maintaining optimal performance and durability.. Key Features. Extension case providing stable housi