Merc Mercury Alpha 1 Gen II (Alpha I Gen 2) I/O Sterndrive Aluminum Anode Kit with Hardware Complete Anode Kit and Hardware for Mercury Mercruiser Alpha 1 Gen 2 Sterndrive Includes Mounting Bolts Aluminum Anode good for Saltwater & Bracking Water Known as Zincs in Boating World But New Aluminum Material Lighter More Resistant Merc Mercruiser Now Reccomends Aluminum Anodes on their Drives