Color is not claimed as a feature of the mark.
The mark consists of On a black background, "brass knuckles" depicted in stark black and white with the four "impacting" knuckles surfaces facing the viewer. Each of the four "impacting" knuckles surfaces is white, and a single capital letter in black appears on each of the four surfaces. From left to right, these letters are "A", "C", "A" and "B".