Quartet 1950's Fivre Brown Base Blue Label 6V6GT Vacuum Tubes
Here is a quartet (4 pcs.) of vintage FIVRE 6V6GT vacuum tubes.
These are the 1950's brown base, blue label version which was the top of the line.
They have been thoroughly tested on our calibrated Hickok 533A tube tester with excellent results as follows: 4,200, 4,400, 4,600, and 4,700 µMhos (4,100 µMhos = 100% Gm)