The second generation of the Mazda MX-5 Miata, internally known as the NB, was introduced for the 1999 model year. It retained the 1.8-liter engine of the earlier car, but it was visually distinct from the earlier car due to more rounded styling - most notably with the fixed headlamps replacing the older model's retractable headlamps. A mild facelift arrived in 2001 - and with the facelift came an additional 15 horsepower (143) via variable valve timing. Notable variants include the 10th Anniversary Edition, and the powerful Mazdaspeed MX-5 Miata, introduced in 2004. The NB was replaced by the NC generation for model year 2006.