This temporary and portable anode is easy to move and a convenient way to add extra corrosion protection to your boat. The Grouper weighs 5.65 lbs. and comes complete with a 15 foot vinyl coated cable and clip. It is an ideal way to provide temporary extra corrosion protection to your boat or engine when mooring in different water environments. Using the cable on a cleat, secure the Grouper's weight below the bottom of the hull before attaching the alligator clip to outboard or outdrive mounting bolt, or rudder or strut ground strap, etc.

When the anode is 70% eroded it needs to be replaced.

Martyr (Canada Metal - Pacific Limited) only uses mil-spec mil-a-l800l alloy in all of their premium marine anodes. This alloy contains mostly zinc but also contains parts of cadium (0.1%) and aluminum (0.25%) the cadium helps the anode erode inward giving the anode a sandblasted appearance.

Canada Metal uses a special steel combination fastener that makes it possible to use their Balldrive, which is a hex driver with a universal ball tip.

What causes corrosion? Seawater is a good conductor and freshwater a bad conductor, so corrosion is worse in seawater. Generally, corrosion rates increase in proportion to the amount of oxygen in the water. However, cracks and crevices, which are areas starved of oxygen, become anodic and corrode also. Higher temperature increases corrosion rates - doubling for every 30 degrees C (55 degrees F). There are various types of microorganisms that can contribute to corrosion, either by removing protection or causing a corrosive environment.

Why do I need anodes? You need anodes on your engine because when two different metals are in contact, electrons will flow from the more negatively charged metal (anode) to the more positive metal (cathode). If you want to protect both types of metal from corrosion, you must add a third metal such as zinc, although magnesium and aluminum are also used. This active metal becomes the anode for both metals. The zinc or aluminum sacrifices itself to protect the other two metals, hence the term "sacrificial anode".