Neodymium Disc Magnet 30 x 30 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. It is noticeably stronger than conventional ferrite magnets and generally has a protective coating because the material is prone to corrosion. N48 indicates the magnetic grade; a higher number generally means a stronger magnet, with grades commonly ranging from N35 to N52.
 
The larger size suits more demanding tasks, including strong attachments, handling, assembly and robust projects, also in industrial environments. The actual hold depends on the contact surface and the thickness of the metal. Holding force is greater on thick steel than on thin sheet metal.
 
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.