1.High load carrying capacity 2.High speed 3.noncontact seal 4.good quality ... speeds and are robust in operation, requiring little maintenance.2)Deep raceway grooves and the close conformity between the ... lubrication role:(1) reducing friction, reducing wear and tear(2) use time growth, also increase its life period(3) ... and low costVarious size and designs. ball bearing 6020,nsk deep groove ball bearing