Neodymium Block Magnet 40 x 20 x 5 mm N52
 
An NdFeB (neodymium) magnet provides high magnetic attraction for its size, making it useful for technical projects, DIY and industrial applications. Compared with ferrite, neodymium provides much greater magnetic attraction. A protective surface coating helps improve durability. N52 indicates the magnetic grade. The usual range is N35 to N52, with higher numbers generally indicating greater magnetic attraction. The rectangular shape is useful for frames, edges and applications requiring an elongated, stable magnet.
 
The larger design suits demanding applications, including attachments with high magnetic attraction, grippers and professional use. Holding force depends strongly on the thickness and condition of the metal surface. It is greater on thick steel than on thin sheet metal.
 
Warning: keep out of reach of children. Magnets can snap together suddenly, pinch skin and chip or break on impact. Handle them carefully when bringing them together or separating them. Keep them away from bank cards, sensitive electronics and medical devices.