Within a 1/8 inch (.32cm) olive drab border a pentagon 1 13/16 inches (4.60cm) on a side, divided per saltire and charged with the letter "A" 1 7/8 inches (4.76cm) in height, all counterchanged red and white.
The insignia is in the colors of an army. The division per saltire and the five sides of the pentagon are suggestive of the numerical designation of the organization while the letter "A" indicates that the organization is an army.
The shoulder sleeve insignia was approved on 26 Oct 1944. (TIOH Drawing Number A-1-365)