5B/255M CV391 STC UK röhre early type double square getter,welded plate,matched

Description

Vintage tubes STC,United Kingdom,matched quad NOS tested
Early version with double square getter,welded plate
Tested on Roetest V10.1 (72mA=100%)
Tube 1 : 72mA    6mA/V
Tube 2 : 70mA    6.25mA/V
Tube 3 : 69mA    5.62mA/V
Tube 4 : 72mA    6mA/V
No shorts,no gas
I will pack
the tubes properly(in a wooden box), and will take great care in doing so
PRICE IS FOR
4 TUBES