A wartime Leica IIIc red shutter
The first 1576 IIIc's produced in 1939 have German black shutter blinds. After serial number 362,401 Leitz used material originally obtained from Kodak in 1937 which was dyed red on one side. This material had been part of research into production of heat-resistant shutters. By 1941, according to van Hasbroeck, the supply of Kodak red shutter blinds had been exhausted and Leitz resorted to use of German produced black material produced from parachute cloth begining with serial #379,226. By that time, about 14,000 IIIc cameras had been manufactured with red blind material which was nearly half of the total wartime production. Presumably the vast majority of these cameras had their shutters replaced with black material.
This claim that the red material was originally obtained from Kodak may be related to the claim of Lahue & Bailey that it was obtained from Graflex. Although Graflex had become independent of Kodak in 1926, the latter authors may have found information that linked the supply of red shutter material to both Graflex and Kodak. However, Lahue & Bailey are clearly in error when they claim that the material was used only in rare post-WWII IIIc models.
The red shutter models of the IIIc are uncommon though perhaps not rare, and command premium prices on the collector market these days. However, few if any fake wartime IIIc's are known to exist since they had the stepped upper housing which was expensive to copy. None the less, an authentic red curtain IIIc will draw a 50-100% premium over those cameras that have the conventional black shutters. There have been a few documented attempts to color the front curtain but these were usually the result of restorations of authentic wartime IIIc's.