McVitie Weston valve collection, Tungsram valve, type PV3018
Tungsram valve, type PV3018, (RMW/A170 - McVitie Weston number), by Tungsram Electric Lamp Works (Gt. Britain) Ltd.
Tungsram valve, type PV3018, (RMW/A170 - McVitie Weston number), by Tungsram Electric Lamp Works (Gt. Britain) Ltd.