... row tapered roller bearing,double row tapered roller bearing ,deep groove ball bearing,cylindrical roller bearing,automobile tensioner bearing and bearing wheel kits).Please ... :Gcr15(Chrome steel)--China3)Shield/Closure of deep groove bearing:Plain(Open),Z,ZZ,RS,2RS4)Vibration and Noisy level ... of deep groove bearing :Z1,Z2,Z3,ZV1,ZV2,ZV3Z1V1,Z2V2,Z3V35)Precision ...