... and specially condition.The rings and balls made by full ceramic material:Zr02,as a standard constructure,the cage made ... PEEK,PI,AISI SUS304,SUS316,Cu,etc. 6901-2RS Full Ceramic sealed Ball Bearing, the inner diameter is 12mm, outer diameter ... applications, Bearing is made of ZrO2 Ceramic Zirconium oxideItem: 6901-2RS Ball BearingType: Full Ceramic Ball BearingCage: PTFEBalls: ZRO2 CeramicClosures: ...