This image is released under a CC BY-NC-SA 4.0 Licence
Buy this image as a print
License this image for commercial use at Science and Society Picture Library
SMG00237640 Science Museum Group © The Board of Trustees of the Science Museum
Wade Bequest collection of valves: early indirectly heated triode radio valve by Marconi-Osram with pip top and B4-3 base plus side terminal. With paper label: W67.