10 C. Postal stamp Merkur head and 90 C. Special stamp \"140. Birthday of Gregory from Tours\" with hand stamp overprint in type I, properly franked mixed franking on letter from \"Dunkerque 16.07.40\" to Ghyvelde with on the back arrival stamp from 17.07.1940, faultless condition, unsigned, expertise Lothar Herbst VP (2018) : \"the condition is perfect. The stamps are only in very small number of pieces known, therefore are they very rare. \", Michel 1.000.-