US Air Force Henry "Red" Erwin, Kadena AB Japan Challenge Coin Measures Approximately: 1.50 InchesScalloped EdgingFront: Erwin Airman Leadership School, Air Power Through EducationBack: Henry "Red" Erwin, Kadena Air Base, Okinawa, JapanChallenge Coins are generally created for the Military and are prized by the service members that receive them. Perfect for Collectors of Militaria.