Distinctive unit insignia (U.S. Army)

A distinctive unit insignia (DUI) is a metallic heraldic badge or device worn by soldiers in the United States Army. The DUI design is derived from the coat of arms authorized for a unit. DUIs may also be called "distinctive insignia" (DI), a "crest" or a "unit crest" by soldiers or collectors. The term "crest" however, in addition to being incorrect, may be misleading, as a DUI is an insignia in its own right rather than a heraldic crest. The term "crest" properly refers to the portion of an achievement of arms which stands atop the helmet over the shield of arms. (Nevertheless, a minority of DUIs happen to depict crests, such as those of many National Guard state area commands.) The U.S. Army Institute of Heraldry is responsible for the design, development and authorization of all DUIs.

Pre-World War I Insignia. Distinctive ornamentation of a design desired by the organization was authorized for wear on the Mess Jacket uniform by designated organizations (staff corps, departments, corps of artillery, and infantry and cavalry regiments) per General Order 132 dated December 31, 1902. The distinctive ornamentation was described later as coats of arms, pins and devices. The authority continued until omitted in the Army uniform regulation dated December 26, 1911.

Distinctive unit insignia. Circular 161 dated 29 April 1920 authorized the use of the regimental coat of arms or badge as approved by the War Department for wear on the collar of the white uniform and the lapels of the mess jacket. Circular 244, 1921 states: "It has been approved, in principle, that regiments of the Regular Army and National Guard may wear distinctive badges or trimmings on their uniforms as a means of promoting esprit de corps and keeping alive historical traditions. Various organizations which carry colors or standards have generally submitted coats of arms having certain historical significance. As fast as approved these coats of arms will for the basis for regimental colors or standards which will eventually replace the present regimental colors or standards when these wear out. The use of these coats of arms as collar ornaments in lieu of the insignia of corps, departments, or arms of service would be an example of distinctive badge to be worn by the regiment." `The first unit to wear this insignia was the 51st Artillery which received approval for wear on March 18, 1922. It was designed by Master Gunner and Master Sergeant Edward C. Kuhn, the artist responsible for creating all authorized coats of arms and distinctive unit insignia at the time.

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