Neodymium magnet, also called NdFeB magnet, is a tetragonal crystal formed by neodymium, iron, and boron (Nd2Fe14B). This kind of magnet is the most commonly used rare earth magnet and is widely used in electronic products, such as hard drives, mobile phones, earphones, and battery-powered tools. N35 and N52 magnets are two common grades of neodymium magnets.