23160-ZZ5-000ZA Case *Nh8* - Overview. The 23160-ZZ5-000ZA Case *Nh8* is an essential component in Honda marine engine systems. It serves as the primary gear case, playing a critical role in housing and protecting the primary gears that drive the propulsion. Designed specifically to operate within Honda's marine engine setups, it ensures seamless integration with existing parts, maintaining optimal performance and durability.. Key Features. Primary gear case component essential for the mechanica