Zinc

We specialize in zinc and aluminum anodes for: 
Ship Hull Anodes
Ship Tank Anodes
Pier, Dock, Jetty or Wharf anodes
Boiler anodes
Condenser anodes

Sacrificial anode

A sacrificial anode, or sacrificial rod, is a metallic anode used in cathodic protection where it is intended to be dissolved to protect other metallic components.

In laymen's terms, it is a piece of more readily-corrodible metal attached by a conductive solid to a less readily-corrodible metal, with both metals immersed in a conductive liquid, typically fresh or salt water. The more active metal corrodes first and generally must oxidize nearly completely (hence the term "sacrificial") before the less active metal will corrode, thus acting as a barrier against corrosion for the protected metal.
More scientifically, a sacrificial anode can be defined as a metal that is more easily oxidized than the protected metal. Electrons are stripped from the anode and conducted to the protected metal, which becomes the cathode. The cathode is protected from corroding, i.e., oxidizing, because reduction rather than oxidation takes place on its surface.

For example when zinc and iron are put together (in contact) in the presence of oxygen and water, the zinc will lose electrons and go into solution as zinc cations. Electrons released from the zinc atoms flow by metallic conduction to the iron where, on the surface, dissolved oxygen is reduced, by gaining the electrons released by the zinc, to hydroxide anions. Were the zinc not present, the same reduction of oxygen to hydroxide would occur on the iron surface; however, in that case, the electrons for reduction would be furnished by the iron thus oxidizing the iron. Therefore, the zinc, when present, is "sacrificed" by being oxidized instead of the iron. The iron is "safe" until all of the zinc has corroded.