6304-2RS Sealed Ball Bearings 20mm x 52mm x 15mm Lot of 10 Bearings 6304-2RS Sealed Ball Bearings, the inner diameter is 20mm, outer diameter is 52mm and the width is 15mm, each bearing has 2 Rubber Seals to protect the bearing from dust or any possible contamination, also bearings are pre-lubricated with grease, Bearings are made of Chrome Steel.