50 C. Charity issue \"Musica - with new overprinted value+20 C. \" with hand stamp overprint in type I, properly franked multiple franking on letter from Ghyvelde. 07.1940 to Dunkerque with on the back arrival stamp from 8.07.1940, in perfect condition, expertise Lothar Herbst VP (2019) : \"the condition is perfect. The stamps are only in very small number of pieces known, therefore are they very rare. Multiple franking with charity stamps are very rare. \", Michel 1.200.-