Precision grade ABEC-1, max rpm 34000 with grease. Pre-lubricated with grease, less friction, no maintenance needed Single-row radial ball bearing for applications that support radial and axial loads Easily removed and reinstalled.perfect for moderate load uses: skateboards, Inline skates, scooters, inline blade electric motors, wheels of bicycle, motorcycle, electric hand power tool ect. in many other rolling applications Repalcing the worned ones on your skatebord scooter inline blade electric motors, wheels of bicycle & motorcycle,automobile, electric hand power tools, etc in many other rolling applications. Please do check dimensions/size or the precision grade if it fits in on your device. This 608-2RS miniature radial ball bearing has red double seals and a steel cage, and conforms to the ABEC 1 precision standard. This light duty bearing has an 8 mm bore diameter, a 22 mm outside diameter, and a 7 mm width. Its precision is rated at ABEC 1 by the Annular Bearings Engineers Committee (ABEC), allowing higher speeds and creating lower friction than less-precise ball bearings, and its radial internal clearance is C3 for radial slack between the inner and outer rings is greater than CN (normal) to compensate for thermal expansion.heat treated to increase hardness for wear resistance. Its deep ball grooves in both races support high radial and axial loads,its straight bore fits conventional cylindrical shafts, and its nylon cage prevents the balls from coming into contact with each other during use, reducing friction, vibration, and noise. Removable single lip contact seals on both sides protect against contaminants and retain lubrication applied at manufacture. This ball bearing is suitable for use in skate boarding, inline skating, and other skating applications. colour:Silver + black Material:Carbon steel size:Product size: 8x22x7mm Package Contents: 50* 608-2RS C3 bearings