... .3mm3Steel backing 0.7-2.3mm4Tin-plating 0.005mm or copper plating 0.008mmCHARACTERISTIC:1.No or less lubrication is used ... course of movement. favorable protection forgrinding bearing no grip appearance.7.Less requirement for grinding bearing, all the bearings that not hardening ... , tobacco machine, micro-machine, automobile, motorcycle, agriculture machine. SF-1DU oilless lubricant bearing