Though the AC company were making middle-class saloon/tourers and fast sports cars, their entry into the micro car field was more of a re-entry. After all they had started life with their Autocarrier commercial trikes and passenger sociables in the early years of the century. But they made the mistake of making their Petite look too much like their government-sponsored invalid trikes for general public acceptance. They were current between 1953 and 1958.

The engine was a 346cc single cylinder two-stroke Villiers, there was a three-speed column gearchange, hydraulic brakes, independent springing, and the bodywork was aluminium. Early cars has 8-inch wheels but later ones boasted 12-inch wheels which gave it a very good ride for the type. Top speed was just short of 50mph, consumption 60-70mpg. They were not cheap at just under £400 and only a dozen or so are known to survive.