U.S. military "Colonel" pin

1980s-1990s Silver tone full bird "Colonel" rank insignia pin. Used by U.S. Army, Marine Corps, Air Force, & Space Force branches. "Captain" rank insignia for Navy & Coast Guard. Back of pin has V-21-N for hallmark code issued by U.S. Institute of Heraldry for official military use made by Vanguard Industries. Pin is nickel plated measuring 2x4cm.