This is a great RCA 6SJ7 vacuum tube.  This tube is vintage with metal bodies, and should sound great in your amp. It was manufactured to rigorous industrial standards, so you can expect low noise and microphonics. It has a black metal body and yellow lettering. These are excellent RCA 6SJ7 tubes that are highly sought after, act quickly before they sell out!! More available upon request.

Be carefyl buying tubes from other sellers who list "matched pairs" but do not provide test results or specify the equipment that they use to test the tubes.

I personally tested these tubes on my recently calibrated Hickok 600a tube tester and the results are as follows:

2,475