(!!) PT-210 GE Pliotron Balloon engraved base NOS 1920”s (29ma Gm=2000) (rare)

PT-210 GE Pliotron Balloon engraved base NOS 1920”s thoriated tungsten filament like 10Y

tube in very good condition

29ma

Gm=2000

NOT A PAIR

STRONG SINGLE

Good curent range 20-30ma

Good Gm = 1600-1800

Vplate=300V

Vgrid=-15V