miniature v groove bearing :1,ABEC-3,5;Z2V2,Z3V3 2,High speed 3,End cover:ZZ,RS 4,Noise level: ... ,C0,C3... Lily bearing is a specialized manufacturer of miniature v groove bearing. Features:1),Shield / closure: Open,Teflon Sealed,Rubber Seals ... ,2 Metal Shield2),Tolerance codes: ABEC-1, ABEC-3, ABEC-5, ...