I had one of those when I was a young lad in the days when Hillman Imps and Minxes ruled the roads. It was a short-lived innovation - each track contained a lengthy coiled spring, with each hut having a motor which turned cogs into the coils of the spring to push it round the track. You also got a set of pegs and sticker pads, so you could fix a peg onto the base of any toy car, drop it into the spring and then watch it whizz round the track. You could reverse the direction of either circuit (for a road with traffic in both directions, and run lots of cars/lorries etc at the same time) or run them in the same direction as a race track (which is what I did most of the time, but I had a longer track with equal lengths). Its advantage was fairly cheap compared to eg Scalextric as it did not need special cars - you could use your ordinary favourites out of the toybox. Disadvantage in my case was one motor always ran slightly faster than the other, so racing was too predictable outcome. Also the spring was fairly clumsy for making extended tracks - you could get extra lengths and connectors, but not as versatile as other track systems.

It was fun for what it was but desirability was quickly overtaken by Hot Wheels and other (Corgi Rockets, Matchbox Superfast) plastic track systems at end of 60s.

Not quite the same thing, but did anyone have a Hot Wheels Sizzler set?? I did, but same problem - some cars were always faster than others, so racing was again impossible.