Magnesium Anode kit made by Tecnoseal, one of the worlds leading suppliers of sacrificial anodes for cathodic protection in the leisure boat market.
The kit for the Mercruiser alpha one generation 2 sterndrive comprises of 2 trim collar anodes, a cavitation plate anode, a block anode, an engine collar anode and an engine plate anode, along with the required fixings, ie all the factory fitted anodes.
Aluminium anodes are suitable for salt and brackish water situations and are recommended by many outdrive manufacturers, please check your manufacturers recommendations