FXX is the track version of the Enzo
Not all of them are red - #16 is silver, #17 is white, #21 is the Solar Direct car and it is orange, #22 is Giallo Modena, #24 is TDF Blue, #28 is black, #30 is the Schumacher car and it is black with no stripe. There are also more non-red ones, but they don't have numbers on them so I can't organize the pics I have of them, and yes I am aware of how OCD I am.