1938 3rd Reich Special registered cover commemorating to Graf Zeppelin´s 100th birthday / anniversary. Very decorative piece  with two Zeppelin commemorative airpost stamps Michelnumber 669 and 670 and a special commemorative cancel Frankfurt 8.7.38. Registered label Frankfurt Flug- und Luftschiffhafen. Siegernumber  0455 VIII B Real usage adressed to  Mainz with arrival postmark on the back. See scans.