Swabia 1912, transfer trip Frankfurt - Oos 31.5, droped Karlsruhe Rueppur, extreme scarce, contemporary used brass sheet metal card "ZEPPELIN airship in the full flights" with 5 Pfg Germania and date stamp Karlsruhe Rueppur 31.5 with alongside very clear blue violet on board confirmation mark 31.5, short "Greeting from Zeppelin . " and signature of the passenger, these metal installation cards are in contemporary use only in very few copies known, excellent condition, signature Buehler (former starting price 1000)