Since 1872, a single silver bar has served as the rank insignia for 1st Lieutenants in the Army and for all officers in the O-2 grade in the other branches of the United States Armed Forces.
Prior to the introduction of the black beret as the standard headgear for the combat uniform in 2001 and the Army Service Uniform in 2004, the 1LT insignia was worn on the Garrison Cap, which was originally introduced in France as the “Overseas Cap” during World War I. When the Garrison Cap was replaced by the beret, the insignia was (and is still) worn centered on the beret flash.
But the Garrison Cap made a comeback in 2018 with the introduction of the Army Green Service Uniform. First Lieutenants and other Officers wear their rank of insignia on the left side of the “curtain,” the upturned lower portion of the cap, 1 inch from the front crease (see
Figure 21–7 in the January 2021 edition of DA PAM 670-1).
More Army 1st Lieutenant Rank Insignias