A Gold color metal and enamel device 1 1/8 inches (2.86 cm) in height consisting of a shield blazoned: Gules on a saltire Or voided of the field a fleur-de-lis of the second. Attached below and to the sides of the shield a Gold scroll inscribed "QUOD HABEMUS DEFENDEMUS" in Black letters.
The red of the shield signifies Air Defense Artillery. The outline in gold of the saltire or diagonal cross denotes that the Regiment was organized in the south; viz: The Coast Defenses of Charleston, Pensacola, Key West and Galveston. The saltire is taken from the battle flag of the Confederacy and, as only its outline appears on the shield, denotes a suggestion of the south. The fleur-de-lis stands for the service in France of the 121st Company, C.A.C. (Battery C, 61st Regiment, C.A.C.). The motto translates to What We Hold We Will Defend."
The distinctive unit insignia was originally approved for the 13th Coast Artillery Regiment on 11 August 1924. It was redesignated for the 13th Artillery Group on 20 November 1967. The insignia was amended to add the motto on 20 November 1967. It was redesignated for the 13th Air Defense Artillery Group on 4 April 1972.