In Europe, although most national championships (British, French, German and the Spanish-based International GT Open) run under FIA/ACO GT regulations with some modifications to ensure closer racing and lower costs, some championships are open to non-homologated GT cars. The Belcar series in Belgium allows silhouettes and touring cars to race alongside GTs, while the VdeV Modern Endurance allows small prototypes from national championships such as the Norma, Centenari and Radical to race alongside GT3 class cars. Britcar permits a wide range of touring and GT cars to compete in endurance races, and Britsports permits various kinds of sports racer.