Ball Bearings 3/16" x 3/8" x 1/8" With Ceramic Balls Lot of 10 Bearings 10 Ball Bearings with Ceramic Balls , this is a popular size that could be used in many application that uses this size 3/16" x 3/8" x 1/8", each bearing has 2 metal shields to protect the bearing from dust or any possible contamination, also bearings are pre-lubricated with grease, Ceramic Balls are the highest standard of balls that can make your bearings live at least 5 times more than any other bearings