Since 1775, NCOs have been set apart from other enlisted Soldiers by distinctive insignia of grade. The insignia evolved throughout the years. In 1821, regulation changes prompted the use of stripes, or chevrons, to be worn pointing upwards on the sleeves. In 1851, a uniform change directed that chevrons point downward. In addition, the chevrons also changed size and color frequently. Finally, in June 1958, the Army instituted the chevron system still in use today.