Gear differential accuracy interior gears made from brand new graphite composite combination. Includes 2 bevel gears and 4 satellite gears. Molded from the all-new special lightweight and extra-strong graphite material gives the gears an optimum stability of hardness, toughness, and freedom to provide endurance, minimal wear, and minimizing breakage or teeth stripping. The graphite gears are lighter which results in increased drivetrain efficiency. A must have for professional racers. Fits T4.