McVitie Weston valve collection, STC valve, type 4251A
- Made:
- 1933
STC valve, type 4251A, double-ended glass envelope 1ft 8in length overall, 6in diam with ceramic end caps, lower end-grid connector, upper end filament connector, with supporting strap/anode connector, (RMW/J117 - McVitie Weston number), by Standard Telephones and Cables Limited, 1933.
