Designed to secure your downrigger to the T joints on rails of boats with narrow gunwales. Machined aluminum construction, powder coated to resist corrosion.Perfect mount for “T” joints on rails or narrow gunwales.Adapts to tubing up to 1.5 or 40mmCompatible with all Cannon Downriggers (except Mini-Troll), subject to the strength of the tubing it is mounted onMaterial: Aluminum