Set of 24 empty envelopes sent to from France to a French inmate in Lager Helmholz in Düren (Rheinland) . All the letters are missing, but it's difficult to find post from this prisoner camp in Düren. All the envelopes are complete with French stamps with the image of Verdun hero and then French betrayer Phillipe Petain. Also ink stamp "Ae" is visible in many envelopes and censorship ink stamps too. All sent in the 40s. Düren was completely destroyed by allies during the heavy air raids of 1944. Condition is very good.