Green beret
U.S. Special Forces wear the green beret as a distinction of excellence and uniqueness within the Army.
United States military beret flash
It is not clear when beret flashes began to be used by the US Army. However, US Army films between 1956 and 1962 suggest beret flashes may have been introduced around 1961, when the green beret was officially authorized for wear by members of the US Army Special Forces.