45 C. Postal stamp "Merkur head and 55 C. Postal stamp "peace allegory" with overprint in type I, properly franked mixed franking on small-format, charming ladies letter from "Dunkerque 16.07.1940" to Ghyvelde with reverse arrival postmark from "17.07.1940", faultless condition, 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 1.100.-