... ) 2.Quality standard:ISO9001:20000 3.Satisfactory qualiy,sevice cylindrical roller bearinglow vibration,low noise,low friction moment,long service life ... ,6907,6908,6909,691016000series:16001,16002,16003,16005,160073)Sealing form:OPEN,RS,2RS,Z,ZZ,RZ,2RZ,N,NR4)Material ...