Brand New and high qualityMade of Carbon SteelWidespread bearing,economic and standard.Easy Installation & ReplacementLess Friction, Higher Speeds. Durable & InsulationSize: Inner diameter: 8mmOuter diameter: 22mmThickness: 7mmQuantity:40pcsPackage Included:4x Set (40pcs) Ball BearingsOnly the above package content, other products are not included.Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.