Mercury – Magnesium Gearcase Anode | Corrosion Protection | Magnesium | 8M0179229Mercury Magnesium Gearcase Anode Corrosion Protection Magnesium 8M0179229 Overview Theres a certain kind of quiet confidence that comes when your outboard is protected the right wayespecially if you spend your time on freshwater lakes where corrosion creeps up slowly and quietly. You dont notice it on that sunny morning when you idle away from the dock, but you feel it years later if the engine wasnt protected. Thats why a good anode isnt just a small