87121-ZVT-G10 RR (105) MARK - Overview. The 87121-ZVT-G10 RR (105) MARK is a genuine Honda marine engine part designed to serve as a rear mark identifier within the engine rigging and accessories system. It plays an important role in marking and supporting system components, ensuring proper alignment and identification during maintenance or assembly. As an OEM component, it guarantees seamless integration with existing hardware, maintaining optimal performance and durability for Honda marine eng