... Closure:Plain(Open),Z,ZZ,RS,2RS,UG.5)Vibration and Noisy level: Z1,Z2,Z3,ZV1 ... .Z3V3.6)Precision level:ABEC-1,ABEC-3,ABEC-5.7)Fields Used in : Motorcycle , Motor , Pump ... ,Sewing machine,Massage Chairs,Textile machinery, Electric tools,Agriculture machinery ,Fitness equipment , Washing Machine,Vacuum Cleaner,Office ... Groove;4. Precision Grade: P0, P6, P5, P4;5. Clearance Grsde: C2, C0, C3, C4, C5;6 ...