Mather stands a respectable even six feet, and weighs just over 200 lbs.  He dresses in a manner that would help him blend in with the average spaceport crowd.  He has a gun holstered on each hip whenever he is out in public.   It's not clear whether they are traditional ballistic or radiation-based.  Lights flashing in his eyes would clue the casual observer in to the fact that he relies on a cybernetic HUD.  At least, most of the time.  When he's feeling more at ease with his surroundings, he often turns the program off.