1 Fr. Charity issue "Marshal F. Foch" with overprint Type I, variety "inverted overprint", franked single stamp on a letter from "Ghyvelde 8. 07. 1940" to Dunkirk, with arrival postmark on the reverse dated "9. 07. 1940", flawless condition, expertise by Lothar Herbst VP (2018) "The condition is impeccable. The stamps are known in very small quantities, therefore they are very rare, especially stamps with inverted overprint.", Michel 1. 500.-