A gold color rectangular metal and enamel device 1 1/8 inches (2.86cm) in height and 1 inch (2.54cm) in width, consisting of a scarlet background on which is centered horizontally a green stripe 3/8 inch (.95cm) in width.
Symbolism: Subsequent to the Mexican War and until the blue uniform was abolished, the Band of the Fourth Infantry was authorized to wear a scarlet piping on the chevrons and trousers stripes in commemoration of the Regiment’s distinguished service in the battle of Monterey in turning a captured battery of artillery against the enemy. The scarlet perpetuates this distinguished service of an element of the Regiment. Green is the predominating color of the coat of arms of the Regiment; it also symbolizes the service of the Fourth Infantry in the Mexican War.
Background: On 19 February 1925 the unit was permitted to wear the red-green-red distinctive unit insignia as a cloth tab on the shoulder. The metal and enamel distinctive unit insignia was originally approved on 21 Dec 1987. It was amended on 14 Sep 1989 to revise the description and clarify the symbolism.