The SMBN0475 block neodymium magnet is made from high-performance N42 NdFeB, with Nickel coating. The dimension of this item is 3/8″ length × 3/4″ width × 1/4″ thick, with step OUT, magnetized through thickness, with a tolerance of ±0.004″ × ±0.004″. The weight of this super strong neodymium magnet is 0.020875 lbs. It can pull up to 15.71 lbs steel. And the surface field is up to 4216 gausses.