McVitie Weston valve collection, Tetrode valve
Tetrode valve, metallizing removed, (RMW/G147 - McVitie Weston number), by Tungsram Electric Lamp Works (Gt. Britain) Ltd..
Tetrode valve, metallizing removed, (RMW/G147 - McVitie Weston number), by Tungsram Electric Lamp Works (Gt. Britain) Ltd..