Working again with Thomas, Mays developed the TT design in 1994 at the Volkswagen Group Design Center in California where he was Audi design director. It was first shown as a concept car at the 1995 Frankfurt Motor Show. When the TT went on sale in 1998, its distinctive curved roof and high beltline helped spark a revival of the Audi brand, and its timeless simplicity is properly considered a classic.