The SMDN0179 disc neodymium magnet is made from high performance N42 NdFeB, with Nickel coating. The dimension of this item is 15/16″ dia. × 1/16″ thick, magnetized through thickness, with tolerance of ±0.004″ × ±0.004″. The weight of this super strong neodymium magnet is 0.0116875 lbs. It can pull up to 6.2 lbs steel. And the surface field is up to 879 gausses.