Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Soviet Union - Pioneer Flights - 1927 (September 16), Pioneer Flight cover from Moscow to Berlin, franked by Lenin Mourning imperf stamp of 6k (medium frame) and the Haag Conference 10k and 15k, the last one with a spot on ''A'' in ''Avio...'' variety, red boxed ''Mit Luftpost...'' and Berlin next day arrival ds, F/VF and scarce franking, Est. $150 -$200, Scott #266, C1-11 var