【30 lb horseshoe magnet】Width: 1.77", Height: 1.18", Depth: 1.18", Space Between Poles: 0.88. Nail polish magnet will not naturally demagnetize over time. 【Strong Alnico Magnet】Nail polish magnet horseshoe is made of three layers of Ni+Cu+Ni. The 30 lb pull magnet of these industrial grade magnet makes it perfect for lifting, holding, sorting, clamping or retrieving steel or iron parts 【For Scientific Experiments】Explore polarity, attraction, and repulsion. Great for hands-on science investigations, STEM projects, classroom labs, science fair, science clubs, home school, and more! 【Hole in top + Removable keeper】This 30 lb magnet horseshoe nail polish has a smooth surface with a hole on top for attaching to conveyors, racks, welding jigs, and other applications. 30 lb horseshoe magnet for nails will retain their magnetic force indefinitely; removable keepers insure a long life and optimum performance 【Multipurpose U horseshoe shaped magnet】Coating are built for heavy duty use and will not naturally demagnetize over time. It can also use to doing velvet nails, fishing something, measuring, collecting small metal screws, doing experiments, etc Strong Alnico Magnet