The Austin-Healey 100S was a series of limited production, aluminium-bodied cars introduced in 1955. The 100S derived from the BN1 100, and was developed for racing, with the 'S' in the name referring to the famous Sebring racetrack. These special cars saw improvements to the drivetrain and engine, and were built in limited numbers, with only 50 production cars sold. An additional five examples were built as prototypes and development cars. Production of the Austin-Healey 100S ended before the end of 1955.