106pcs Plastic Gear Rack Pulley Worm Gearbox for DIY Projects and Experiments
Contains a variety of different types of gear, all can be consistent with each other, modulus 0.5, the hole was 1.9mm, 2.05 (2.0) mm, 2.4 (2.55) mm, 2.9 (3) mm and so on. Also includes hexagonal gears, racks, pulleys, belts, axles and other DIY accessories.
Gear diameter formula:
gear diameter (addendum circle) = (number of teeth + 2) x modulus