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) of the American Bearing Manufacturers Association (ABMA). There are five classes, going from widest tolerances to tightest: 1, 3, 5, 7, and 9. Higher ABEC classes provide better precision, efficiency, and greater speed capabilities, but do not necessarily mean that the bearing can spin faster.
Additionally, the ABEC rating does not specify many other critical factors, such as smoothness of the rolling contact surfaces, ball precision, and material quality.
Zoty-Rose
Rose
Taylor
Bella
Jeremy
Daisy
Doris