Osram Osglim Neon lamp valve, flat plate 1.25in x 2in in glass envelope, bayonet cap, (RMW/K7 - McVitie Weston number), by Osram, c.1928.
Osram Osglim Neon lamp valve, flat plate 1.25in x 2in in glass envelope, bayonet cap, (RMW/K7 - McVitie Weston number), by Osram, c.1928.