정확하게는 Tungsram에서 제조한 것인데...
Tungsram의 역사가 아래와 같습니다. 뮬라드가 1952년 영국 Tungram의 경영권을 획득했다고 나오네요.
Tungsram of Tottenham, London
1933 Private company established, a subsidiary of the United Incandescent Co of Budapest, manufactured valves by importing and sealing of parts made elsewhere.
WWII: started production of valve components that it could not purchase.
1952 Controlling interest acquired by Philips Electrical Ltd . Mullard took over management of British Tungsram.
1961 Manufacturers of wireless and other valves, industrial and domestic lamps.