Wade Bequest collection of valves: early triode radio valve by Marconi-Osram
Wade Bequest collection of valves: early directly-heated triode radio valve by Marconi-Osram with pip top and B4-3 base. With paper label: W61.
Wade Bequest collection of valves: early directly-heated triode radio valve by Marconi-Osram with pip top and B4-3 base. With paper label: W61.