TESLA EZ80 "NOS" 9 pin, 6.3V. Made in Czech Republic
EZ80 / 6V4 "NOS" TESLA valve, in original box. Double diode rectifier valve. It is used as a full wave rectifier for radio receivers. Made in the Czech Republic. Better than any current production or Russian valves. Tesla valves were relabeled and sold by Siemens, Valvo, Telefunken, etc.