1,groove ball bearing 2,High speed 3,End cover:ZZ,RS 4,Noise level:Z1, ... 5,C2,C0,C3... groove ball bearing HX Bearings manufacture precision ball bearings from 3mm to 500mm O.D. Production standards ... 10mmInch Series Bore sizes 0.0781 to 0.375 inches high precision deep groove ball bearing