Neodymium Disc Magnet 20 x 1 mm N48
 
A neodymium magnet (NdFeB) is small but very strong. It is made from a special alloy and magnetised in a strong magnetic field during manufacture. Neodymium is much stronger than ferrite, and its protective coating helps prevent corrosion. N48 indicates the magnetic grade; NdFeB grades commonly range from N35 to N52, with higher numbers generally indicating stronger magnets.
 
At Ø20 × 1 mm, this magnet provides a good hold on metal and is useful at home, in workshops and for a variety of projects. The metal material and thickness strongly affect performance. A thicker, flatter surface gives a better hold.
 
Warning: keep away from children. Two magnets can snap together quickly, pinch fingers and crack or chip. Use spacers for storage and take care when separating them. Keep them away from sensitive electronics, cards and medical devices.