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SMG00313282 Science Museum Group © The Board of Trustees of the Science Museum
Frelat Triode valve, cylindrical glass envelope with top pip Science Museum Group © The Board of Trustees of the Science Museum
Frelat Triode valve, cylindrical glass envelope with top pip, heavily Mg* gettered 4-pin metal and Paxolin* base, (RMW/Y36 - McVitie Weston number), by Frelat N.V..