Brass articulated (multi-piece) construction Staff NCO shoulder scales. A special shoulder scale was worn by non-commissioned officers of the regimental staff. This was distinct in that it had a pattern of rivets on the surface of the scale and were wider and thicker through the crescent than standard enlisted scales. The underside also had a bottom piece that the common privates scales lacked. The sergeants wearing this pattern included the Sergeant Major, Regimental Quartermaster Sergeant, and Regimental Commissary Sergeant. Exact reproduction of originals worn on the shoulders of the dress uniform.
Shoulder scales were originally designed to be a form of body armor. The idea was that if a soldier wearing these was struck down by a swordsman, the blow would be diminished by the protecting scales. However, by the American Civil War these scales were worn by Enlisted and NCOs as part of their dress uniform and not for protection.