There are two accepted coat colours, red and blue. Chocolate and cream are considered to be faults. Blue dogs can be blue, blue mottled, or blue speckled with tan on the legs and chest and white markings and a black patch or 'mask' on one or both sides of the head. The mask consists of a black patch over one or both eyes (for the blue coat colour) or a red patch over one or both eyes (for the red coat colour). Depending on whether one or both eyes have a patch, these are called, respectively, 'single' (or 'half') mask and 'double' (or 'full') mask. The breed standards of the Australian, American and Canadian kennel clubs specify that the Australian Cattle Dog should have a natural, long, un-docked tail. There will often be a solid colour spot at the base of the tail and a white tip. The tail should be set moderately low, following the slope of the back.