The SMBN0522 block neodymium magnet is made from high performance N42SH NdFeB, with Nickel coating. The dimension of this item is 1″ × 1/2″ × 1/2″ thick, magnetized through thickness, with a tolerance of ±0.004″ × ±0.004″ × ±0.004″. The weight of this super strong neodymium magnet is 0.0675 lbs. It can pull up to 31.01 lbs steel. And the surface field is up to 5248 gausses.