This is a life-size full length-oil portrait, painted almost entirely from life sittings. Photographs were taken to finish the details of the uniform. In this case, the subject didn't "sit", but actually stood at parade rest for several sessions. The artist does not expect this kind of endurance from most subjects, and does, actually, let sitters sit, and even rest often.
Rangers will recongnize the coin at the soldier's feet.

"Specialist Stephen Bennis"
oil on linen, 82" x 40", 2002