Neodymium Block Magnet 25 x 20 x 8 mm N35
 
Neodymium (NdFeB) is among the strongest magnetic materials and provides substantial holding force for its size. It is much stronger than conventional ferrite magnets and generally has a protective coating because the material can corrode over time. N35 indicates the magnetic grade. The usual range is N35 to N52, with higher numbers generally indicating greater magnetic attraction. The rectangular block shape is practical for assembly. It is easy to align, provides a good contact surface and fits well into fixtures and grooves.
 
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: not suitable for children. Two magnets can snap together quickly, pinch fingers and crack or chip. Separate them carefully and avoid impacts. Keep them away from bank cards, sensitive electronics and medical devices.