The SMRN0659 ring neodymium magnet is made from high-performance N42 NdFeB, with Nickel coating. The dimension of this item is 3/8" od × 1/8" id × 1/8" thick, magnetized through thickness, with the tolerance of ±0.004" × ±0.004" × ±0.004". The weight of this super strong neodymium magnet is 0.003325 lbs. It can pull up to 4.05 lbs steel.
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