Above you can see two examples of Faller slot car models. They came is several different colours. As you can see, in the track are two metal wires running through which runs a electrical current. The cars in turn pick up the current and contain small engines so can drive through the track.

Below you can see any small boys christmas dream in the 1960s, a complete gift box containing two cars and some track. Another set is known containing just the one car (4001). Both sets could be expanded by buying extra tracks etc. I think both would be on my christmaslist as well!