A premium quartet of 6L6 power tubes, rare and desirable double getter tubes. Made in the USA (Sylvania) and branded  Peavey Super 6 for their guitar amps. These are some of the best 6L6's made and sound fantastic! These all test very strong and are closely matched at 5500-5700 mhos, with 5000 being average for a new tube.  All tested on a recently refurbished TV-10 tube tester.