McVitie Weston valve collection, Brimar valve, type 6A7
Brimar valve, type 6A7, (RMW/Y321 - McVitie Weston number), by Standard Telephones and Cables Limited.
Brimar valve, type 6A7, (RMW/Y321 - McVitie Weston number), by Standard Telephones and Cables Limited.