The Isetta is an Italian-designed microcar built under licence in a number of different countries, including Spain, Belgium, France, Brazil, Germany, and the United Kingdom. Because of its egg shape and bubble-like windows, it became known as a bubble car, a name later given to other similar vehicles. The BMW Isetta was in 1955 the world's first mass-production 3-Litres/100 km car. It was the top-selling single-cylinder car in the world, with 161,728 units sold. __TOC__