The red horseshoe is the universal symbol of magnets recognized around the world. Each magnet includes a keeper to help retain magnetic power. More About Alnico: Made from aluminum, nickel, cobalt and iron, alnico is primarily used for magnetic applications requiring a high heat tolerance. More common applications include educational and scientific experiments, magnetos, coin acceptors, clutches and bearings, relays, generators, loudspeakers, guitar pickups and cow magnets.