1.Series:HI series,NTN series,etc. 2.ISO 9001:2008 3.Mold:OPEN,Z, ... ,RS,2RS 4.OEM Supplier Specifications: 1.Series:HI series,NTN series,etc. 2.Tolerance:ABEC-1 ABEC-3 ABEC-5 ... wheel bearing, Joint bearings, Linear Bearings etc. NameEccentric BearingSeriesHI series,NTN series,etc. MaterialChrome steel ,carbon steel ,Gcr15 SealingOPEN,Z,ZZ ...