10 C. Postage stamps issue "Merkur head" and 90 cent charity issue "unemployed children" with hand stamp overprint in type I, properly franked mixed franking on First Day Cover from "Dunkerque 01.07.40" to Ghyvelde with on the back arrival cancel from 02.07.1940, very fine, expertized Calves, Dreyfus, Roumet and expertise Lothar Herbst VP (2025) "the condition is perfect. The stamps are only in very small number of pieces known, therefore are they very rare. ", Michel 1.000.-