R1038ZZ Shielded Ball Bearings 3/8" x 5/8" x 5/32" inch 10 Ball Bearings R1038ZZ Shielded Ball Bearings, this is a popular size that could be used in many applications that uses this size 3/8" x 5/8" x 5/32" inch. Bearings are 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.