I'm not sure, but think they are illegal in the US. On some cars they are a third light on the rear. On the diablo I think they are where the back up lights are. You have one that's a back up light and the other one is a fog light. They are red in color and I think the reason we don't have them here is so that people don't think your breaking...

Just like in FL where we get down pours with zero visibility they don't want you to turn on your emer flashers, because if you need to brake the person vehind you will not know your breaking...

Maybe someone else could chime in...