DUI for the 121st Infantry Regiment, also for use by Headquarters, 48th Infantry Brigade Combat Team. 
Description/Blazon
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.
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