90109-ZV4-000 Bolt Special (8X20) - Overview. The 90109-ZV4-000 Bolt Special (8X20) is a specialized fastener designed for Honda marine engine systems, crucial for securing components with precision and durability. This bolt plays a vital role in maintaining the integrity and reliable operation of Honda's active marine and rigging systems. Engineered to meet factory specifications, it ensures seamless integration with existing parts, maintaining optimal performance and durability.. Key Features.