Zinc
Leah, A zinc is used to protect metals, like shaft, prop, engine lower unit, from stray electrical currents. It is not placed on your boat (however some larger boats do have zincs on the hull, but I'm sure your C22 doesn't need one). If you have an outboard motor and your boat is in the water for the whole summer, AND you leave it in the 'down' position on the motor bracket, you would need a zinc on the skeg. If you tilt your motor up out of the water, then you won't need one. Also, if you trailer the boat and don't keep it in the water, you don't need a zinc. RP..
