Item: 608 Full Ceramic Ball Bearing Type: Full Ceramic Ball Bearing Cage: PTFE Balls: ZrO2 Ceramic Inner/outer races: ZrO2 Ceramic Dimensions: 8mm x 22mm x 7mm/Metric ID (inner diameter)/Bore: 8mm OD (outer diameter): 22mm Width/Height/thickness: 7mm Package: 1pcs 608 ZrO2 full ceramic ball bearing 22x8x7mm Zr02 ceramic bearings for bicycle