This set contains four plastic gears for hobby, craft or science projects. Plastic gears can be used to show gear reduction in motorized equipment or adjust the direction of rotation. Many different products such as watches, clocks, and cars require gears to function properly.
Large Gear = 41.2 mm diameter with 40 teeth
Medium Gear = 31.2 mm diameter with 30 teeth
Small Gear = 21.2 mm diameter with 20 teeth
Motor Gear = 12.9 mm diameter with 12 teeth
The motor gear in this set has a 2 mm bore so that it can be connected to miniature DC motors. All other gears have a 1/8" bore and are compatible with the 1/8 inch the Axle Rods under product code: PWHEELS.