Type I
Stearing mechanism: Gear wheel
Guidance pins: Metal
Rear axle: Brass gear wheels

Versions with smokeglass and driver application

Type II
Stearing mechanism: Gear wheel *
Guidance pins: Plastic
Rear axle: Brass gear wheels
Smokeglass

* more fragile than Type I

Type III
Stearing mechanism: Rubber hose
Guidance pins: Plastic
Rear axle: Plastic gear wheels

Versions with smokeglass and driver application

Obstacle car
In the picture below you can see the difference between a normal Type I car and an obstacle car (right). The obstacle car has an extra capacitor mounted (blue in the picture), and 2 identical slidebrushes.