Mercury - Quicksilver Aluminum Anodes Corrosion Protection Component Transom Plate Nuts 55989Q9. Overview. Corrosion protection starts with the right anodes, and the Mercury Marine 55989Q9 Quicksilver Aluminum Anodes are designed to keep your MerCruiser's transom assembly protected from galvanic corrosion. Made for MerCruiser MC-I, R, MR, Alpha, and Bravo drives (serial No. 0D469828 and below), these cast aluminum anodes meet strict military standards for strength and durability. They're easy to