I purchased this postcard some time back and decided to do some research on it as it was interesting.
1917 RPPC Postcard Stable Sgt. Reuben A. Pratt – Largest Man in the U.S.N.G.
Mexican Border Service Colorado US National Guard
Excellent hand written caption on the back, "Stable Sgt. Ruben A. Pratt of Colo Troop Mexican Border service 1917. The largest man in the U.S.N.G. Height 6' 9" Weight 260 lbs.."