MG DUFF Aluminium Anode kit for a Mercruiser Alpha 1 Gen 2 Outdrive/Sterndrive. Suitable for use in ALL waters including Salt, Fresh and Brackish! Complete with all required anodes and Stainless Steel fixing bolts to suit. To tell the difference between Gen 1 and Gen 2 drives, look at the rams. On Gen 1, the rams taper slightly. On Gen 2 rams are parallell. The advantages of using aluminium anodes over are: Voltage - Aluminium anodes generate a lower voltage (-1.1v) than zinc (-1.03), providing increased protection Longer life - Aluminium anodes will last longer 30% - 50% longer than Zinc. The Ampere Hour Capacity (AHC) per pound weight of aluminium alloy is 1150 AHC compared to 368 for Zinc. Lighter - Aluminium is 2 1/2 times lighter than Zinc! Eco-Friendly - Aluminium alloy does not pollute. Re-Immersion - Aluminium alloy works immediately upon re-immersion because the aluminium hydoxide is porous. Zinc Hyroxide is impermeable and must be burnished off before the Zinc anode is effective. Waters - Aluminium anodes are suitable for fresh, salt and brackish waters and is as equally effective in each! Boat - Aluminium anodes can be used on any material, GRP, Steel, Alloy without fear of overprotecting.