1 Mark on 10 penny airmail with overprint \"Gelber Hund\", impeccable mint never hinged and having very fresh colours, unsigned with photo certificate Mary Brettl BPP \"faultless condition. Entirely mint never hinged, without hinge. \", Michel 2.500.- we obtained for a comparable copy in of our 186. Auction 1.400.- Euro as well percentage of bid price!