Yamaha Trim Tab Skeg Anode Corrosion Protection 6K1-45371-02-00. Overview. Corrosion is one of the biggest enemies of any outboard running in saltwater, and the trim tab anode is designed to take that hit before your engine does. The Yamaha Trim Tab Skeg Anode 6K1-45371-02-00 helps protect critical lower unit components by sacrificing itself to corrosive elements in the water. It mounts directly to the trim tab location and works continuously while the engine is in use or sitting at the dock. Fo