Roller Bearings Marterial: Gcr15 Seal material: Rubber,Ferrum Noise: Z1,Z2,Z3 ... ) 60 series : 607, 608, 6000, 6000, 6001, 6002, 6003, 6004, 6005, 6006, 6007, 6008, 6009, 6010, 6011 3) 62 series : 626 ... , 69097) Inch size series: R6, R8, EE3, EE48) Specifc designed bearings for motorcycle Double row Tapered roller ...