50 Heller exhibition stamp Kaschau, vertical pair from the right margin with vertical, right-lying dark pink handstamps "Karlsbad 1. X. 1938 + Swastika", postmarked KARLSBAD 1 4. X. 38 4 d on a piece of mail, flawless condition, edition of only 118 pairs, expertized by Mahr BPP and photo certificate Brunel VP (2014) "The condition is impeccable... so far eight pieces with vertical imprints are known", Michel 4. 000.-