Matched Pair of SYLVANIA JHS-6X4WA tubes CV4005 6X4W 6X4 EC90 U78
made in USA in 1956 (same code 642)
Full Wave Rectifer Power supply tubes
Tubes seem to be unused, NOS, tested like new tubes, perfectly balanced and matched.
tube 1 Ia = 54mA/54mA (135%)
tube 2 Ia = 52mA/52mA (130%)
where 40mA is 100% for the new tubes
Black plates, D-getter. Both tubes have 642 date code
I think it would be the great idea to rewire the socket in your amplifier using rather poor sounding
Chinese 6Z4 or Russian 6C4P which are same tubes as 6X4
but have different pinout, as you can see at one of the pictures -
you will only need to rewire pin 7 to pin 6 and pin 5 to pin 7
or just use 6X4 to 6Z4 adapter
so you will be able to use great sounding 6X4 tubes
even GEC CV4005 or Marconi U78
price is for the matched pair
I always send the tubes by priority registered mail with tracking number within hours after receiving payment