Galvanic corrosion has given boat owners concern for more than a century. We know that when different metals are exposed to each other in salt water, one of them will corrode excessively.
This happens because one metal is less noble than the other. Propellers, shafts, rudders, struts, etc., can be cathodically protected at the expense of zinc plates and anodes.
All of our zinc anodes are cast from special alloy zinc that meets Military Specification MIL-A-18001K.
Hand poured zinc has a higher degree of porosity due to its molecular make-up than die cast zinc. This is important because in hand poured zinc, size for size, there is a greater area exposed to corrosion than in die cast zinc.