Mercury - MerCathode Anode Assembly Corrosion Protection System OEM Coated Metal 8M0181304. Overview. When you run big power on the water, corrosion protection becomes more than maintenance-it becomes peace of mind. The Mercury 8M0181304 MerCathode Anode Assembly gives you that steady confidence every time you fire up your V10 or V12. It is the small but critical safeguard that helps you trust your engine whether you are cruising the shoreline or pushing hard miles offshore. Knowing your MerCath