Velocity 28's: Shielded, Replacement Aerospace Ceramic, Hybrid AXLE BEARINGS offer the most speed and excitement to any 1/28 scale RC racer. Better corner entry, exit and blistering acceleration! RWD chassis with 3mm FRONT AXLES Requires: 7 bearings. (4) 3mm fronts, (3) 3mm rears. Reduce slop, noise increase consistency and be faster too. You won't find a better bearing for this price.