The SMBN0437 block neodymium magnet is made from high performance N42 NdFeB, with Nickel coating. The dimension of this item is 1/2″ × 1/4″ × 1″ thick, magnetized through thickness, with tolerance of ±0.004″ × ±0.004″ × ±0.004″. The weight of this super strong neodymium magnet is 0.03375 lbs. It can pull up to 10.54 lbs steel. And the surface field is up to 6474 gausses.