2 x 6V6gt RCA Tubes*Zenith *Smoked Glass*Strong Matched Pair*#4
2 x 6V6gt RCA Tubes. Tested on enhanced Triplet E3444 Laboratory tester by Paul Hart of Ga. Made in USA for Zenith. Smoked Glass. Tubes may also be operated under the test conditions for extended periods to be sure that it is stable.