R168-2RS Sealed Ball Bearings 1/4" x 3/8" x 1/8" inch Lot of 10 Bearings R168-2RS Sealed Ball Bearings, this is a popular size that could be used in many application that uses this size 1/4" x 3/8" x 1/8" inch. Bearings are made of Chrome Steel, each bearing has 2 Rubber Seal to protect the bearing from dust or any possible contamination, also bearings are pre-lubricated with grease.