41100-ZVT-910ZB Gear NH565 Case - Overview. The 41100-ZVT-910ZB Gear NH565 Case is an essential component in Honda marine engine systems. This gearbox casing serves as the durable protective housing for the gears within the lower unit of Honda outboard motors, ensuring smooth mechanical motion and reliable operation. Engineered to fit seamlessly and function flawlessly with OEM Honda components, it ensures seamless integration with existing parts, maintaining optimal performance and durability..