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
Western Electric valve, type 242C Science Museum Group © The Board of Trustees of the Science Museum
Western Electric valve, type 242C, large cylindrical glass envelope, marked 354551, (RMW/D118 - McVitie Weston number), by Western Electric Company Limited, c. 1937.