Features: The bearings are made of high carbon steel, don't worry about durability and resistance to deformity under heavy loads during jump, slide and impact. As you know it is easy to get dust and soil into the bearing which will slow down the bearing while we are sliding outdoor. Bust Bearing with on both sides will keep contaminants out and save our bearings. Suitable for skateboards wheels, scooters, Longboards, Roller Skates or other skating applications etc. With a smooth surfaces and clear engraving, these bearings not only provide a professional look but also ensure low noise and high rotational speed. These bearings will significantly improve your overall performances and productivity. Get yours today experience difference! Specifications: Material:Carbon Steel/Iron Type:A/B/C/D Size:Approx.22x7mm/0.86x0.27inches Package Includes: 10Pcs Ball Bearings note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item.