This Radio Shack XMODS Generation 1 bearing provides replacement bearings for this radio control vehicle. It has a 3 mm inside diameter, a 6 mm outside diameter, and a 2 mm depth. Ball Bearings for RadioShack Xmods 1/28 Upgrade, that’s the number one upgrade for any Xmods car, Bearings set Contains 14 Bearings, bearings are protected by metal shields from both sides, also bearings are pre-lubricated with grease. These are hard to find bearings, since they are covered with metal shields. Dirt will never go inside the bearings again, you don’t need to oil the bearings anymore or even clean them.