6350 Sylvania made for IBM black plates "U" getter halo used/good 1950's, faded printing in white box

1 section) 9.2ma Gm=4400

1 section) 9.7ma Gm=4400

Tested on Amplitrex

Vplate=150V

Vgrid=-5V

Good used Ma per section = 7-10ma

Good used Gm per section = 4000-4500

Recommended for

- VTL Wotan MB1250, VTL MB450, VTL MB300, VTL 225 Deluxe, VTL Deluxe 140, VTL Stereo 120/50, VTL ST150
- VTL Siegfried
- Joule Electra LA-150 (mk2)

- Joule Electra LA 100 Mk.III

- Shindo-lab Corton