"Tank Periscope"
France, c. 1940-50, Bakelite, metal and mirror. Tank periscope or episcope, optical instrument used by the army in France. Equipped with a case and two 45° mirrors, this device allows you to observe without being seen at a certain distance, used above crowds or in ambushes. Good condition, some visible defects on the mirrors. 
Le Magazine de PROANTIC
TRÉSORS Magazine
Rivista Artiquariato