... coefficient of friction, high limiting speed, large size range and various structure.2.Features : Shield / closure: ... , AISI304, AISI316, ceramicRetainer: PTFE, nylon, PEEK or stainless steelHardness for rings and balls: 59 - 63HRCBall bearings bore ... , Motor , Pump ,Fan,Air conditioner ,Microwave Oven,Range hood,Sewing machine,Massage Chairs,Textile machinery, Electric tools,Agriculture machinery ...