This is the Robinson Racing 32-pitch 9-tooth pinion gear.
Features: Standard alloy 32 pitch pinion gears are a great replacement for many Kyosho cars and any cars that use 32 pitch pinion gears
Includes: One Robinson Racing 32 Pitch 9 Tooth Pinion Gear with set screw
Inner Diameter: 1/8 (3mm)
Outer Diameter: 0.33 (8.5mm)