Nazi typewriter by Mars Buromaschinen, Berlin circa 1935-40
This was 'liberated' by my late father, Percy Reynolds. He was a Dane and had fled Denmark to join the RAF, serving in Burma. After the war he joined British intelligence and served in Berlin, where he came across the typewriter.
There is a 'secret' key - pressing the numeral 3 key with the shift key down, the Nazi SS lightning flash insignia is printed (inset, enlarged).
Whereas all of the numeral keys show their 'shift' character above the main numeral (eg, %, &, ", = etc), the 3 key is strangely, and almost disturbingly, blank... giving nothing away of grim letters which had rolled through this otherwise innocuous machine.
Dad served in Berlin, surviving a kipnap attempt by the KGB, before marrying my mother, a German girl, Christa Schmidt-Weferlingen.
My mother's brother Bernd was in the German infantry and was killed in 1942 on the Eastern Front. We have a letter notifying my grandmother of his death, seemingly typed on a very similar typewriter.
Dad served in the British Embassy in Bonn, until the family moved to England in 1955.