Maker's Name: 
general Electric
Where made: 
3.7 × 3.7 × 11 cm

The valve is a sweep tube ie horizontal line output tube, used in colour TV. Colour TV with CRT tubes used EHT voltages up to 35kV to generate a beam of electrons adequate to illuminate the colour pixels on the CRT screen. Thus to deflect the beam required a lot of energy. This valve is typical of those required to do this job. This valve was also popular with radio hams as an output amplifying tube in HF transmitters, either singly or up to four in parallel. They were much cheaper than valves specifically designed for this purpose.