The SMAN0801 neodymium arc magnet is made from super strong N52 NdFeB, coated with Nickel as neodymium magnets get oxidized easily. The dimension of this big neodymium magnet is 2” O.R. × 1” I.R. × 1” × 30°, magnetized Magnetized thru circumference; the weight is about 0.22 lbs. It can pull up about 300 times the weight of steel, 74.6 lbs. The surface field of this item is 7210 gauss, a super high level resulted by high thickness through the magnetic direction.