Marine Sergeant Major E9 Challenge Coin This challenge coin is 1.75" antique brass with a real rope edge. The front of the coin has a blue ring with the words "Semper Fidelis" at the top and "Sergeant Major" at the bottom. The middle of the coin has a black background and features the rank insignia in full color. The back of the coin has a 3D Eagle, Globe, and Anchor in antique brass on a scarlet background and "United States Marine Corps" surrounding the center.