Imperial bearings ID:1.984mm-12.700mm Material:GCr15,S45C,9Cr18 and Ceramic Low noise ,high speed,long life time used Imperial deep groove ball bearing1.Model:Open,Z,2Z,RS,2RS,RZ,2RZ2.Quality level:Reach the same level as the Japanese and European bearings3.Tolerance level:ABEC-1(P0),ABEC-3(P6),ABEC-5(P5),ABEC-7(P4)4.Noise Level:EMQ V1 Z2, EMO V2,Z3, EMQ V3 Z4,EMQ V45.Vibration level:V1,V2,V3,V46 ...