The Cow Magnet Applicator is primarily used to prevent hardware disease in cows. Hardware disease is caused by cows inadvertently eating metal like nails, staples and baling wire, and then the metal settles in the reticulum. Cow magnet, also known as the rumen magnet, cow stomach magnet, or cattle magnet, is a veterinary medical device for the prevention of hardware disease. It is an eco friendly permanent magnet that removes iron components from a cow. Cow Magnet Applicator is very effective.