8-pc Hooks made with Strongest Magnet - Neodymium Magnet, 8 to 10 times stronger than ceramic magnet * 16mm (5/8") Diameter x 37.5 mm (1.48") tall with M4 threaded hook attached * Steel cup offers protection for magnet and make the magnetic force concentrated on the magnet surface. * Industrial applications such as fastening, holding, hanging objects, etc. * Holding Power: over 24 lbs, durable Nickel-Copper-Nickel 3-layer Coated magnet