Mercury - Zinc Anode Corrosion Protection Component Marine-Grade Zinc 47820A1. Overview. Salt and water can be tough on an outboard, but corrosion doesn't stand a chance when your anodes are doing their job. The Mercury Marine 47820A1 Zinc Anode protects your Mercury 200HP carbureted TwoStroke outboard by sacrificing itself to corrosion before it reaches your prop, gearcase, or other vital metal components. Made from high-quality zinc and built to Mercury's factory specs, this OEM anode kit incl