Canada Metal zincs are composed of an alloy that meets Mil-Spec MIL-A-18001 for sacrificial anodes. This alloy is mostly zinc, but with measurable concentrations of cadmium (~0.1%) and aluminum (~0.25%).

The additional cadmium causes the anode to erode from the surface inward, which causes a ''sandblasted'' appearance to the surface. When the anode is almost dissolved, it needs to be replaced.