Fear of the potential use of chemical warfare agents made the gasmask and canister a constant companion of the German soldier through-out the war. Each soldiers was issued four skin decontamination tablet containers with ten tablets per container along with their gasmask and other accessories. Regulations of December 3rd, 1942 stipulated that a colored adhesive tape was to be applied to the skin decontamination tablet containers to indicate year of production with red tape indicating production up to 1940, black tape for 1941, light green tape for 1942 and yellow tape for 1943.
The example here is in as found condition dated 1941 and with black tape on it.