Wool bunting swallowtail flag. The flag is horizontally divided into two equal fields, one above the other: the top field is red, the bottom field is white. There is a blue border around all sides of the flag except the hoist. In the center of the flag are two yellow crossed cannons surmounted by a black cartridge box. On the front flap of the cartridge box is a gold plate with the letters "US" written inside. Above this plate, on the front flap, is "FORTY ROUNDS" written in white letters. White hoist with an inscription reading "Brg / Art'y 15 Army Corps."