6 x 12 x 4 Shielded Ball Bearing Snap Ring Groove One Bearing 6 x 12 x 4 Shielded Wheel Ball Bearing for many applications, bearing has Snap Ring Groove, this is a popular size that could be used in many RC Cars and Trucks, 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.