The ABEC scale is an industry accepted standard for the tolerances of a ball bearing. It was developed by the Annular Bearing Engineering Committee (ABEC). Generally, the higher the number on the scale ABEC 1, 3, 5, 7 and 9 the better the precision and accuracy, but not necessarily a smoother bearing. The best bearings are from reputable brands such as ABEC 11 or Bones.
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