Neodymium Magnet in Steel Housing with Countersunk Hole 50 x 13,5 x 5 mm. 
 
Neodymium (NdFeB) is among the strongest magnetic materials and provides substantial holding force for its size. Compared with ferrite, neodymium provides much greater magnetic attraction. A protective surface coating helps improve durability. The N indicates the magnetic grade, commonly ranging from N35 to N52. Higher numbers generally indicate greater magnetic attraction. This magnet with a Mounting Hole for easy installation in a frame, holder or panel.
 
The 50×13,5×5 mm block is suitable where a substantial but manageable hold is needed in workshops. For good results, use a flat, clean metal surface. Any gap caused by thick paint or an uneven surface reduces holding force. Do not overtighten the screw during installation. Neodymium is hard but brittle and can chip or crack under excessive pressure. A washer can help.
 
Warning: keep away from children. Strong attraction can cause pinching injuries, and the magnets may break. Store them with spacers. Keep them away from bank cards, sensitive electronics and medical devices.