This rare and collectible item is a must-have for stamp and postal history enthusiasts. This cover features the first air mail to  SS Leviathan by Adams Air Mail pick up, with a signature by the inventor,Dr. Lytle S Adams included. It has the cancellation of the U.S. German S.P.O on June 12th, 1929.  Its origin can be traced back to the United States in 1929 and its quality is marked as used, with an ungraded certification. With its unique historical value, this item is a great addition to any collection.