McVitie Weston valve collection, STC valve, type V230A/1K
STC valve, type V230A/1K, marked LUI 31, (RMW/Y56 - McVitie Weston number), by Standard Telephones and Cables Limited.
STC valve, type V230A/1K, marked LUI 31, (RMW/Y56 - McVitie Weston number), by Standard Telephones and Cables Limited.