A Gold color metal and enamel device 1 5/32 inches (2.94 cm) in height overall consisting of a shield blazoned: Gules, on a bend Or three oozlefinches Vert. Attached above a wreath Or and Gules, an pi Or around and behind a French locomotive affront Gules. Attached below the shield a Gold scroll inscribed "SUSTINEMUS" in Black letters.
The shield is red for Artillery. The bend is taken from the arms of Lorraine, which is gold with three golden alerions on a red bend, with the colors reversed. The three oozlefinches are used instead of the alerions. The green oozlefinch was the device on the shoulder patch worn by the railway artillery reserve in France, of which this Regiment was a unit. The locomotive and pi show the character of the Regiment. The motto translates to "We Support" and alludes to the mission of railway artillery.
The distinctive unit insignia was originally approved for the 43d Coast Artillery Regiment on 1 February 1937. It was redesignated for the 43d Artillery Regiment on 13 January 1959. The insignia was redesignated for the 43d Air Defense Artillery Regiment effective 1 September 1971. It was amended to correct the symbolism on 17 November 1983.