![](https://coimages.sciencemuseumgroup.org.uk/50/651/large_thumbnail_1927_1074__0001_.jpg)
McVitie Weston valve collection, Mullard valve, type TSP4
- Made:
- 1948
- maker:
- Mullard Limited
![Mullard valve, type TSP4, gold metallizing, marked OB](https://coimages.sciencemuseumgroup.org.uk/455/716/medium_smg00259485.jpg)
Mullard valve, type TSP4, gold metallizing, marked OB, (RMW/Y196C - McVitie Weston number), by Mullard Limited, 1948.
Mullard valve, type TSP4, gold metallizing, marked OB, (RMW/Y196C - McVitie Weston number), by Mullard Limited, 1948.