The first cars built by the Coopers were single-seat 500-cc Formula Three racing cars driven by John Cooper and Eric Brandon, and powered by a JAP motorcycle engine. Since materials were in short supply immediately after World War II, the prototypes were constructed by joining two old Fiat Topolino front-ends together. According to John Cooper, the stroke of genius that would make the Coopers an automotive legend—the location of the engine behind the driver—was merely a practical matter at the time. As the car was powered by a motorcycle engine, they believed it was more convenient to have the engine in the back, driving a chain. In fact there was nothing new about 'mid' engined racing cars but there is no doubt Coopers led the way in popularising what was to become the dominant arrangement for racing cars.