Descriptions<br> This item is made of carbon steel， great replacement for the broken or missing steel balls on the bearing wheel.<br> Ideal accessory parts for bicycle repairing use and rebuilding your bicycle's bottom bracket.<br> Applications would include casters， conveyors， roller skates， bicycles， overhead trolleys， drawer slides， garage doors and door locks.<br> Wholesale purchase would be more preferential.  <br> Specifications<br> Material: carbon steel<br> Color: sliver tone<br> Diameter: 4mm \/ 0.16&amp;quot;<br>  <br> Notes<br> Please allow a bit manual measuring errors.<br>  <br> Package included<br> 240 x 4mm Bicycle Ball Bearings