small steel ball bearings:1,ABEC-3,5;Z2V2,Z3V3 2,High speed 3,End cover:ZZ,RS 4,Noise level:Z1, ... ,C2,C0,C3... Lily bearing is a specialized manufacturer of small steel ball bearings.Features:1),Shield / closure: Open,Teflon Sealed ... Bearings Thrust Ball Bearings Hybrid Ceramic Bearings Hybrid Ceramic Bearings High Performance small steel ball bearings