The 608Ball Bearings can achieve high-speed operation high temperature resistance low noise and smooth rotation making it an ideal choice to meet your bearing needs. Characteristical -- The Bearings are made of Sturdy and durable high-carbon steel don't worry about durability and resistance to deformity under heavy loads during jump slide and impact. -- This bearing effectively prevents dust and debris from entering, protects lubricating oil from being lost reduces bearing noise and ensures normal operation. -- For small motor air conditioning, skateboard, roller skates inline roller skates scooters and small household appliances. Specification Material: High Carbon Steel Dimension: Inner Dia.=8mm Outer Dia.=22mm Thickness=7mm Package Included 20 * 608-2RS Ball Bearings All rolling bearings are open shielded or sealed. Sealed bearings are lubricated with oil or grease in the bearing factory, while open and shielded bearings are meant to be lubricated in place with periodic reapplication of lubrication based on use. WARM TIPS 1) Small dimensional differences may occur due to the measuring method or tool. 2) Due to the difference in screen and lighting the item's color may be slightly different from the picture.