8 x 13 x 4 Shielded Ball Bearings Lot of 10 Bearings 8 x 13 x 4 Shielded Ball Bearings, Bearing is made of Chrome Steel, each bearing has 2 metal shields to protect the bearing from dust or any possible contamination, also bearings are pre-lubricated with grease, Bearings are packed 10 bearings in one plastic tube.