Tin containing Ohropax-antiphones, hearing protection ear plugs, made by Max Negwar, Potsdam, Germany, 1910-1920, as used by personnel during the First World War. Tin containing Ohropax-antiphones 1910-1920
Adjustable double contra angle handpiece, nickel plated brass, by Kaltenbach and Voigt, Potsdam, Germany, 1930-1940 Adjustable double contra angle handpiece 1930-1940