Distinctive Unit Insignia. Description: A Gold metal and enamel device 1 1/16 inches (2.70 cm) in width overall consisting of an "Old Gray Bonnet" Proper. The insignia to be manufactured and worn in pairs.
        Symbolism: The 121st Infantry adopted "The Old Gray Bonnet" as the official air and is known as the "Old Gray Bonnet" Regiment.
         Background: The distinctive unit insignia was originally approved for the 121st Regiment Infantry, Georgia National Guard on 27 June 1928. It was amended to permit manufacturing in pairs on 16 August 1928. It was redesignated for the 162d Tank Battalion, Georgia National Guard on 24 May 1956. The insignia was redesignated for the 121st Infantry, Georgia National Guard on 17 April 1961.

Coat of Arms.
         Blazon:
             Shield: Azure, a saltire Gray fimbriated Or between in fess a prickly pear cactus and a fleur-de-lis of the like.
             Crest: That for the regiments and separate battalions of the Georgia Army National Guard: On a wreath of the colors (Or and Azure) a boar's head erased Gules, in the mouth an oak branch Vert fructed Or.
             Motto: FACIENDUM EST (It Shall Be Done).
         Symbolism:
             Shield: The shield is blue for Infantry. The gray saltire represents service in the Confederate Army during the Civil War. The cactus symbolizes Mexican border duty and the fleur-de-lis service in France during World War I.
             Crest: The crest is that of the Georgia Army National Guard.
             Background: The coat of arms was originally approved for the 121st Regiment Infantry, Georgia National Guard on 26 June 1928. It was redesignated for the 162d Tank Battalion, Georgia National Guard on 24 May 1956. The coat of arms was redesignated for the 121st Infantry, Georgia National Guard on 17 April 1961.