Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Germany - 1912 (June 13), Rhine-Main Air Mail, specially printed orange postcard, franked by dark blue surcharge ''Helber Hund'' 1m on 10pf orange, uprated by Germania 5pf green, tied by Darmstadt ''13.6.12'' date stamp, message is on reverse, VF, Sieger #13, €300, Est. $150-$200, Sc. #CL4