6801-2RS Rubber Seals Ball Bearings 12mm x 21mm x 5mm Lot of 10 Bearings 6801-2RS Rubber Seals Ball Bearings, this is a popular size that could be used in many RC wheel and motor applications that uses this size 12mm x 21mm x 5mm, each bearing has 2 Rubber Seals 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.