A B-17 Flying Fortress in civil aviation servce with Trans World Airline Image stamped on reverse: 'Peter M Bowers.' Printed caption on reverse: 'First plane to carry the new "NL" National Limited License, is this converted Boeing B-17G transport used by TWA as a personnel and executive transport on it's international routes. The NL signifies a limited license, not as severe as the previous NX or NR , granted to aircraft unable to meet full requirments for the unlimited NC. Boeing B-17G, commercial covers on, limited license NL-1B.'