The SL-Class has been German auto company Mercedes Benz's longest and most prestigious brands. Born as a vehicle inspired by the W194 race car, the first ‘sport lightweight' Mercedes-Benz SL introduced in 1954 was noted for its gullwing doors and the first use of fuel injection in a production car. Through decades, the SL-Class has existed as a two-door coupe as well as a convertible. Starting in 2003, the Mercedes-Benz adopted a Vario Roof power retractable hardtop configuration similar to the SLK roadster. From 1998 to 2014, SL-Class performance came from either a V-8 or V-12 engine. In 2015, Mercedes-Benz introduced a twin-turbocharged V-6 powered SL400 to North America. Recapturing elite sports car roots, the Mercedes-Benz SL has offered a high-performance AMG package in the United States since 2003. In recent years, there have been two AMG SL-Class models: the V-8 powered SL55 AMG and the V-12 propelled SL63 AMG.