(1)Shield / closure: Open ball bearing, Z, ZZ, RS, 2RS, 2RZ
(2)Tolerance code: ABEC-1, ABEC-3, ABEC-5, ABEC-7
(3)Vibration level: V4, V3, V2, V1
(4)Radial play: C0, C2, C3, C4
(5)Material: AISI52100, AISI440C, AISI304, AISI316
(6)Retainer: PTFE, nylon, PEEK or (stainless)steel