SR6ZZ Shielded Stainless Steel Ball Bearings, this is a popular size that could be used in many applications that uses this size 3/8" x 7/8" x 9/32" inch. Bearings are made of Stainless 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.