These are optional HPI 0.6 MOD E10 Pinion Gears for the HPI E10 Drifter. A lower tooth count on the pinion gear will give you more acceleration, while a higher tooth count will give you extra top speed. Have a selection of pinion gears available so you can tune the speed of your car as desired!
NOTE: Not compatible with 48 and 64 pitch spur gears.
