Four gears of different sizes, perfect for any investigation or maker project.

• Four gears per set (12, 20, 30, and 40 tooth)
• Larger gears accommodate 4 mm axle, with 3 bushings included to reduce axle size to 2 mm
• All four gears bevelled on one side

Sets include 40, 30 and, 20 tooth gears with 4 mm bore and a 12 tooth gear with a push-fit to a 2 mm motor shaft. There are 3 inserts on each sprue, which allow the 4 mm bore to reduce to a 3 mm bore. All gears are bevelled on one side to allow 90° meshing. The 40 tooth gear has an extra hole to create eccentric movement or for a crank handle (Fits 4 mm dowel).