Mercury - MerCathode Kit Corrosion Protection System Composite Housing 8M0180081. Overview. Anyone who keeps their boat in the water knows the quiet worry that comes with galvanic corrosion. You do everything right-rinse the hull, trim the motor, keep up with service-but salt and stray currents can take their toll. The Quicksilver 8M0180081 MerCathode Kit offers something boaters rarely get: peace of mind that doesn't fade overnight. It actively protects your engine and drive while you sleep, wh