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[2] pr 307A (KR + Sylvania) + [1] NU single

Up for sale are the last of my 307A collection that goes back to a project that I passed on to someone else way back in 2010. I've retested each pair on my Jackson 648S and they're clear for shorts, leaks and have plenty of life left.

First up, the Ken Rads. This pair is actually a triple. All 3 are within 5% on my tester so use two and if/when one goes replace it with another match. If desired I'll label them with the specific values so that the owner can use the two highest testing tubes to start. Asking price is $75+ shipping and any fees. My preferred method is USPS flat rate, but I can accommodate UPS/FedEx it just takes longer to drop them off and longer to arrive (if Ground).

On the tester

The pair

Next up is a matched pair of Sylvanias. Not much to say, they test clear and within 5%. Asking price is $60 + shipping and any fees.


Last is a single National Union branded 307A. Like the others it's been fully tested. That said, I've been around a lot of 307As and only seen two other NU's, hence this tube being a single. No idea if it's worth anything to someone but I'd like to get $25 + shipping/fees for it. Otherwise I'll just turn it into valve art.


Please email me with any questions or offers. I'm a reasonable guy but lowball offers will be cheerfully ignored. I'm confident I'm asking fair if not low prices for fully tested pairs.

Thanks for looking,