Never used, perfect condition.
The matching #'s printed on the boxes are "50ma/4.8ma/v". Included is a paper with the detailed specifications, very thorough. They were produced to carefully match the characteristics, quote, "of the original Western Electric tubes. It's different than the Cetron or Chinese 300b"
"Recommended operating conditions for the average WE and Sovtek 300B:
your tube current on the top of the box is measured under-
Maximum plate dissipation power not to exceed 40watts/tube."
No low ballers and AA Inmates only, included are the new old stock CERAMIC sockets and sealed filament pots.
USA only and includes the shipping charges.