Deep voice (so I guess the vocal chords for that lol)
And yes I'll say it, the man's phallic object
With the exception of the voice, I think my image of a "manly man" that I listed is similar to a Greek statue. They made their statues have definition as if they were athletes, laborers, or something else that meant the man was active and being physical. I think they did it well to portray an ideal manly shape.
... and off the top of my head I can't think of many more 'male' features to be honest, 12 is asking a bit too much. I remeber your 'name 25 things about yourself' question, I ended up answering 'i love anal beads' for about 10 of the things