McVitie Weston valve collection
- Made:
- 1924 in Canada and United States
- maker:
- M-O Valve Company Limited
This image is released under a CC BY-NC-SA 4.0
Licence
Buy this image as a print
BuyLicense this image for commercial use at Science and Society Picture Library
LicenseMarconi 4-electrode valve, type D.E.7
Science Museum Group
© The Board of Trustees of the Science Museum
Marconi 4-electrode valve, type D.E.7., B4+st base, pinch marked DE7, (RMW/G5B - McVitie Weston number), by M-O Valve Co. Limited, 1924.
