The comb is very large and red. A 16 wk pullet might be getting a bit red, but the comb will still be quite small. Male combs are usually red by 8 wks.
Then there is the dark red across the wings, like a rooster badge of honor. The red probably started coming in around 6 wks. Not all males will have this red, it depends on the genes, but the majority of them do. Black and white males will have white patches. Females have smaller, even patterns, generally with muted colors, that makes them look plainer.
Finally, the undisputed male sign are the long, narrow, pointed saddle feathers hanging on either side of the base of the tail. Your guy has white ones. Female feathers in the saddle area are short, wide and blunt and look like the rest of the body feathers. Gives the saddle area a very smooth appearance on females.
