Tecnoseal Rudder Anode - Zinc - 3-3/4" Diameter. Tecnoseal designed these Fishing Accessories with a captive hex nut that prevents water from entering the anode and the full-size design allows for easy replacement without having to remove and replace the salt water protection. The Tecnoseal L3 Rudder Anode is a zinc-based product that guarantees proper functioning and the lightweight design adds to the safety of using these anodes while boating. Pick up a Tecnoseal R3 Rudder Anode for a reliable way to protect your boat from rust and corrosion. Specifications for Tecnoseal R3 Rudder Anode: Manufacturer: Tecnoseal Color: Zinc Package Contents: Tecnoseal R3 Rudder Anode Tecnoseal R3: R3 Rudder Anode - Zinc - 3-3/4" Diameter