are Class 6X (for tapered roller bearings), Class 6,. Class 5, Class 4, . P4. P2. ⎯. ⎯. Ball. ABEC 1. ABEC 3. ABEC 5. ABEC 7. ABEC 9. A60. Bearings. (CLASS
WQK cylindrical roller bearing NNU4052 MP4 1.WQK roller bearing 2.roller bearing manufacturer 3.good quality fair price 4.OEM service. Cylindrical roller
White Paper on bearing tolerance and precision levels including definitions and specifications of ABEC and RBEC precision levels . ABEC 7, Class 4, P4.
ABEC precision levels, ABEC-1, ABEC-3, ABEC-5, ABEC-7, and ABEC-9 are the equivalent to ISO precision levels P0, P6, P5, P4, and P2 respectively.