The Jaguar XK is a two-door 2+2 grand tourer that debuted for the 1997 model year. The XK, which was created as a replacement for the Jaguar XJS, was offered in coupe and convertible body styles. Two generations of the XK were built, the first, which is known as the X100, was offered from the 1997 to 2006 model years, while the second, known as the X150, was available for the 2007 to 2015 model years. The first generation was marketed as the XK8, replacing the XJS. The X100 shared its platform with the Aston Martin DB7 which was itself based on the stillborn XJ41/42 project built on a modified XJ-S chassis conceived in the mid-1980s. The second generation of the XK, noted for its aluminium monocoque chassis and construction, was launched in 2006 for the 2007 model year. The XKR performance variant was introduced in both of the generations with the second generation of the model also boasting a more powerful XKR-S variant. Production of the Jaguar XK ended in 2014, but many late production examples were registered in 2015.