German Luftschutz Black Out Lightbulb (Luftschutzlampe) as issued in many civilian homes during the war to help maintain blackout conditions against air raids. These were recommended by the civil air-raid protection services (RLB). The lightbulb is made by the famous company 'Osram' and is still stored in its original slightly damaged carton box, complete with instruction leaflet. Nice original lightbulb in good condition!