41100-ZVT-710ZB Gear *NH565* Case - Overview. The 41100-ZVT-710ZB Gear *NH565* Case is a critical component within Honda marine engine gear systems. This OEM gear case assembly supports counter-rotation gear functions, ensuring smooth mechanical motion and effective transmission operation. Designed specifically to maintain the integrity and performance of Honda marine engines, it ensures seamless integration with existing parts, maintaining optimal performance and durability.. Key Features. This