[Pantone Value] BlackC/151C [Meaning] A black flag with an orange circle (40 cm in diameter) in the centre informs a driver that his car has a mechanical problem that has the potential to harm him or other drivers and that he must return to his pit. Shown with car number. [Description] 
Black with orange circle
Y e l l o w
G r e e n
R e d
B l u e
W h i t e
B l a c k
C h e q u e r e d
H a l f b l a c k
B l a c k w i t h o r a n g e c i r c l e
Y e l l o w a n d r e d s t r i p e s