thanks for details flare
your message in white :
After the armaments restrictions of the Versailles Treaty, which had forbidden the Reichswehr to own tanks, was for training purposes from 1927 tank exercises with tractors and cars perform as a basis for tank replicas and withwooden dummies. Asa cannon served these chariot replicas a normal flare gun, which was shot by the "cannon barrel". Forthis purpose a cartridge was specially created around 1930, which was called Manöverkartusche für Panzer - Kampfwagen – Nachbildungen (Manoeuvre cartridge for dummytanks). This cartridge contained a black powder charge dammed with a thick layer of felt. In front of the felt layer was a load of powdered cork, in front of it were two cork disks and the cardboard cover. The cartridge produced a blast at the launch, which roughly corresponded to thefiring bang of a small tank cannon. The smoke of the black powder in combination with the cork powder represented the muzzle fire and the muzzle smoke. Manoeuvre cartridge for dummy tanks had anundyed cardboard tube with a brass base. On the side of the case were printed spiral black stripes, the cap was black. All known real pieces are made by Nicolaus factory. Until when exactly the production of such cartridges ran, is not known. In the signallist of 1943 they are still included. Before1935, the cartridges had no inscription, then they were printed.
Your cartridge is a empty instructional case (U = Unterricht,means instruction).