Regarding bearing accuracy classes, besides ISO normal accuracy, as . P6. P5. P4. P2. ⎯. ⎯. Ball. ABEC 1. ABEC 3. ABEC 5. ABEC 7. ABEC 9. A60. Bearings.
White Paper on bearing tolerance and precision levels including definitions and specifications of ABEC and RBEC precision levels . ABEC 3, Class 6, P6.