Iron and magnesium metals, when suspended in an electrolyte (such as salt water), form a galvanic cell—a "battery"—that can generate electricity. When water is added to a ration heater, it dissolves the salt to form a salt-water electrolyte, thereby turning each particle of magnesium and iron into a tiny battery. Because the magnesium and iron particles are in contact, they become thousands of tiny short-circuited batteries, which quickly burn out, producing heat in a process the patent holders call "Supercorroding Galvanic Cells".