The SMBN0434 block neodymium magnet is made from high performance N42 NdFeB, with Nickel coating. The dimension of this item is 1/4″ length × 1/2″ width × 3/16″ thick, with step OUT, magnetized through thickness, with tolerance of ±0.004″ × ±0.004″. The weight of this super strong neodymium magnet is 0.0069375 lbs. It can pull up to 7.01 lbs steel. And the surface field is up to 4556 gausses.