1.High Performance,Long life 2,Competitive price 3,Quick ... :General,flanged,extended inner ring3,Shield / closure: Open,Teflon Sealed,Rubber Seals,2 Metal Shield4,Tolerance codes: ABEC- ... C4, C57,Material: AISI52100, AISI440C, AISI304, AISI316, Ceramic8,Retainer: PTFE, Nylon, PEEK Or Stainless Steel9,Bore Size:from 1mm to ... 0.0781 to 0.375 inches R series High Performance Precision Miniture bearing