40156-ZVT-A10 case (lower) seal c - Overview. The 40156-ZVT-A10 case (lower) seal c is an essential sealing component within Honda marine engine systems. It plays a critical role in preventing water intrusion into the lower unit and maintaining lubrication integrity, thereby supporting the gear case system and its mechanical components to operate reliably and efficiently. Originally designed for Honda marine engines, it ensures seamless integration with existing parts, maintaining optimal perfor