The ABEC scale is a system for rating the manufacturing tolerances of precision bearings. The system was developed by the Annular Bearing Engineering Committee or Council (ABEC) of the American Bearing Manufacturers Association (ABMA). The American Bearing Manufacturers Association was formerly known as the Anti-Friction Bearing Manufacturers Association ABEC equates with precision ball bearing. As the bearing is more precise, the more driving speed you have (1 = normal; 3 middle; 5 = high etc.). High precision doesn´t allow too much tolerance, so the durability go up.

Ball bearings are organized by the ABEC-scale. With this tool the accuracy of the tolerance can be indicated, but not the quality of the material used. Some deep groove ball bearings do not have any ABEC description since 2002 – like these – , but they are produced according to DIN 620. Ball bearings with the description ABEC 1 may have a maximum deviation of 0,008 millimeter accordingly, so ABEC 5 maximum of 0,005 millimeter. These ABEC 9 resp. ABEC 11 bearings are equipollent to the tolerance of ISO class 2/1 and DIN-Norm P2/P1 (see ABEC-scale):