The US Postal History Pioneers of Flight #31 cover featuring CARL A. SPAATZ's flight on June 28, 1980 in Pennsylvania is a collectible piece of aviation history. This handstamped, multi-color cover was originated in the United States and is a unique addition to any postal history collection. With its connection to a prominent figure in aviation and its place of origin in the United States, this cover is a valuable and cherished item for stamp collectors and history enthusiasts alike.