Available here is the card shown in the photographs.

"Sign of Life" card for military addressees (green)

From 1943, the German Reichspost issued special cards that allowed residents of bombed locations to send a short message to their relatives. Two main versions were printed. They have the inscription “Lebenszeichen von . . .” ("Sign of life from . . .") on the front, and “Eilnachricht an . . .” ("Urgent message to . . .") on the back. The cards have a coloured frame around the margins: red cards were for private addressees, green cards for military personnel with field post numbers. This form, often called a “Sign of Life,” might be sent to a serviceman from a bombed city to let him know that his parents were alive after an air raid. The forms were sent free of charge. 

"Lebenszeichen" Karte für militärische Adressaten (grün)
Ab 1943 gab die Deutsche Reichspost Sonderkarten heraus, mit denen Bewohner bombardierter Orte ihren Angehörigen eine Kurznachricht senden konnten. Zwei Hauptversionen wurden gedruckt. Sie tragen die Aufschrift „Lebenszeichen von. . . “ auf der Vorderseite und „ Eilnachricht an. . . ” auf der Rückseite. Die Karten sind farbig umrandet: rote Karten für Privatadressaten, grüne Karten für Militärpersonal mit Feldpostnummer. Diese Form könnte an einen Soldaten aus einer bombardierten Stadt geschickt werden, um ihn darüber zu informieren, dass seine Eltern nach einem Luftangriff am Leben waren. Die Formulare wurden kostenlos verschickt.

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