FR1-4ZZ Flanged Shielded Ball Bearings 5/64" x 1/4" x 9/64" inch 10 Ball Bearings FR1-4ZZ Flanged Shielded Ball Bearings, Bearing inner diameter is 5/64" Inch, Bearing outer diameter is 1/4" Inch and Bearing width is 9/64" Inch, each bearing has 2 metal shields to protect the bearing from dust or any possible contamination, also bearings are pre-lubricated with grease.