100 Pieces of Neodymium Magnet of disc / cylindrical shape N52 magnets with diameter of 3 mm and thickness/height of 10 mm, coated with Nickle (Ni-Cu-Ni). Each Magnet's North and South Pole are on opposite sides of 3mm diameter faces. Pull force of each Magnet is about ~250 Grams. Rare earth neodymium magnets, also known as NdFeB magnets or Neo Magnets, are made from an alloy of neodymium, iron and boron. They are extremely strong even in small sizes. Neodymium Magnets are permanent, and have a high maximum magnetic energy.