Package including 1010 pcs skateboard bearings, size: 8*22*7(inside*outside*height)/unit:mm. MaterialOur 608 ZZ bearing material is made of selected bearing steel. The density of steel is thicker than that of carbon. Therefore, the hardness of the bearing steel is greater, the speed is faster, the friction is resistant, and the service life will be longer. High-quality lubricantsuse lubricants high-speed racing lubricant for pre-lubrication, Ultra-fast lubricant for guaranteed high speeds and minimal friction. The yellow shield seals the lubricant inside the bearing and the wheel. 8mm Ball Bearings Performance Features Bearings Highly hardened bearings, superior load capacity, wear resistance, impact resistance, high temperature resistance, durability and no deformation, to ensure long-term use. High-speed rollingUsed with skateboards, longboards, inline skates , inline skates, electric skateboards and offers the highest accuracy on the market. 36,000 U/min limit with grease lubrication Bearing steel is the best choice.