sealed hub bearings :1,ABEC-3,5;Z2V2,Z3V3 2,High speed ... a specialized manufacturer of sealed hub bearings. Features:1),Shield / closure: Open,Teflon Sealed,Rubber Seals,2 Metal Shield 2),Tolerance codes ... to 30mm Currently, our miniature bearings contains the following types, Metal Shield Bearings Rubber Seals Bearings Teflon Sealed Bearings