6004-2RS Sealed Ball Bearings 20mm x 42mm x 12mm Lot of 10 Bearings 6004-2RS Sealed Ball Bearings, each bearing has 2 Blue Rubber Seals to protect the bearing from dust or any possible contamination, also bearings are pre-lubricated with grease, the inner diameter is 20mm, outer diameter is 42mm and the width is 12mm, Bearings are made of Chrome Steel, Bearings are packed 10 bearings in one plastic tube.