McVitie Weston valve collection
- Made:
- 1924 in United States
BTH general-purpose triode valve, type B3, B4 base, (RMW/C68 - McVitie Weston number), by British Thomson-Houston Company Limited, 1924.
BTH general-purpose triode valve, type B3, B4 base, (RMW/C68 - McVitie Weston number), by British Thomson-Houston Company Limited, 1924.