90603-ZW5-030 Tube (D13) Clamp - Overview. The 90603-ZW5-030 Tube (D13) Clamp is a critical component in Honda marine engine systems designed specifically to securely hold and clamp tubing with a diameter of 13 mm (D13). This clamp plays a vital role in maintaining the integrity of fluid lines within the marine engine setup, ensuring that connections remain stable and leak-free during operation. Engineered to integrate seamlessly with existing Honda marine hardware, it ensures optimal performanc