Made in England by Genalex, these CV4005 are the best of the best! U78 is the special number for the GEC NOS 6X4, and CV4005 is the military number. These have halo getter and same plate structure as all U78. All are in original boxes stamped CV4005!
This is a suitable replacement for any U78 = 6X4 = EZ90 = CV493 = CV4005 = 6202 Full-Wave Rectifier tube type.