MR125 5x12x4mm RC Scale Ball Bearings MR125ZZ  for many applications, this is a popular size that could be used in many RC Cars and Trucks, ABEC-3 Level Bearing is made of Chrome Steel, each bearing has 2 metal shields to protect the bearing from dust or any possible contamination, also bearing is pre-lubricated with grease. inner size 5mm, outer size 12mm, width 4mm. 5x12x4mm ball bearing is for Xray 808 clutch.