McVitie Weston valve collection, Marconi valve, type U12
- maker:
- Marconi Company Limited
Marconi valve, type U12, base marked 346, glass loose, (RMW/A60B - McVitie Weston number), by Marconi Company Limited.
Marconi valve, type U12, base marked 346, glass loose, (RMW/A60B - McVitie Weston number), by Marconi Company Limited.