Cow magnets were originally used as a tool to save the lives of cows, which eat everything from grass and dirt to nails, staples and bits of bailing wire (referred to as tramp iron). A cow has 4 compartments in its stomach, and when these tramp iron items work their way through, they cause “hardware disease”, threatening the surrounding vital organs and causing irritation and inflammation, and worse. The magnet is inserted into the cow’s mouth like a pill by the farmer or a veterinarian and it is designed to lodge in the cow’s second stomach and attract the stray metal on its way by, holding it in a safe place. They also have industrial applications.