The Sprite entered the Austin Healey line-up in 1958 as the entry sports car model developed by BMC (British Motor Corporation) which existed from 1952 to 1966. Conceived as a small sports car for mass appeal, the minimalist engine and undercarriage were designed to keep costs down. Weight reduction was also a focus, and the Sprite adopted the world's first semi-monocoque open body. While the 948cc inline 4-cylinder engine output was only 43ps, this was sufficient power for the 600kg vehicle weight (less than modern 'light vehicles'), which was the highest power to weight in its class at the time. Combined with the rack and pinion steering gearbox, the highly responsive Sprite reaffirmed the pure joy of driving with a lightweight sports car. Produced from 1958 to 1960, the Mk 1 was the most popular model in the series, which was in production for 13 years through to 1971. The Mk 1 not only embodies the elements of the initial development concept of only incorporating parts necessary for driving performance, but also features a distinctive front mask with headlights protruding from the bonnet hood that appealed to many. This feature earned the Mk 1 nicknames such as 'crab eyes' in Japan, 'frog-eye' in England, and 'bug-eye' in the United States.