Tabs of the United States Army

In the United States Army, tabs are cloth and/or metal arches that are worn on U.S. Army uniforms, displaying a word or words signifying a special skill. On the Army Combat Uniform and Army Service Uniform, the tabs are worn above a unit's shoulder sleeve insignia (SSI) and are used to identify a unit's or a soldier's special skill(s) or are worn as part of a unit's SSI as part of its unique heritage.

Source: Wikipedia — Tabs of the United States Army (CC BY-SA 4.0)