McVitie Weston valve collection, Russian Marconi, Round valve
- maker:
- Marconi Company Limited
Russian Marconi, Round valve, marked 3930, (RMW/B18 - McVitie Weston number), by Marconi Company Limited.
Russian Marconi, Round valve, marked 3930, (RMW/B18 - McVitie Weston number), by Marconi Company Limited.