Notes from the set designer
The original designer of this set, ToyGuy816, has made the following comments regarding this set:
"I worked at Mattel between 1970-1975. Around 1973 (or '74?), in response to the first national energy crisis, we were challenged by Management to invent and develop toys utilizing greater amounts of materials other than plastic. Printed cardboard was perfect to provide good looking and effective gravity launches from elevated starts, without having to clamp start ramps to table edges. After this toy happened, I became lovingly referred to as The Cardboard Kid in Preliminary Design. The set including excellent-rolling Red Line cars clearly contributed to its collectability."