Optional tuning gear for the E10. 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-pitch and 64-pitch spur gears.A full selection of 0.6M pinion gears are available to tune the gearing of your E10 for any track type:#88020 PINION GEAR 20 TOOTH (0.6M)#88021 PINION GEAR 21 TOOTH (0.6M)#88023 PINION GEAR 23 TOOTH (0.6M)#88024 PINION GEAR 24 TOOTH (0.6M)#88025 PINION GEAR 25 TOOTH (0.6M)#88026 PINION GEAR 26 TOOTH (0.6M)#88027 PINION GEAR 27 TOOTH (0.6M)#88028 PINION GEAR 28 TOOTH (0.6M)#88029 PINION GEAR 29 TOOTH (0.6M)#88030 PINION GEAR 30 TOOTH (0.6M)#88031 PINION GEAR 31 TOOTH (0.6M)#88032 PINION GEAR 32 TOOTH (0.6M)#88033 PINION GEAR 33 TOOTH (0.6M)#88034 PINION GEAR 34 TOOTH (0.6M)#88035 PINION GEAR 35 TOOTH (0.6M)