1x 20x20mm Potente Imán de Neodimio de Tierras Raras Imán de Varilla Magnética Redonda (L)
When added to Iron (Fe) and Boron (B) (chemical formula Nd14Fe21B) the resultant magnets are the strongest magnets currently available. Neodymium magnets are usually coated Nickel-Copper-Nickel plating to prevent the iron from rusting.