active 1932-1986, manufacturer of meteorological instruments, United Kingdom Francis Barker and Son (1932) Limited 1932 - 1986
1931-1979, recording & consumer electrical/electronic goods manufacturer, United Kingdom Electric and Musical Industries Limited 1931 - 1979
active 1944-1954, laboratory apparatus & instrument maker, London, England W and J George and Becker Limited 1910 - 1954
c. 1908-c. 1957, manufacturer of photographic film and accessories, England Dufay-Chromex Limited 1930 - 1957
1930-1952, audio, phonographic products and magnetic recording manufacturer, Cleveland, United States Brush Development Company 1930 - 1952
1932-1997, aerospace and weapons manufacturer, United States, American Hughes Aircraft Company 1932 - 1997
1930-1994, manufacturer of recording equipment, Arlington, United States Ralph Gerbrands Company 1930 - 1994
1933-1937, manufacturer of radio valves, Highbury, London, England 362 Radio Valve Company Limited 1933 - 1937