High Quality 10 bearings Wheel Ball Bearings for many applications, this is a popular size that could be used in many RC Cars and Trucks, or any application that uses this size 2mm x 5mm x 2.5mm. Bearings are made of Stainless Steel and can rotate up to 99,000 rpm, 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.