These military grade, Joint Army Navy (JAN) vacuum tubes are all new and in the original box. Use as a phase inverter tube in Fender amps. 12AT7's are lower gain than 12AX7's (60 vs. 100) and therefore offer more headroom before pushing the power tubes to break up. You wind up with a slightly lower gain amp, however consider a Champ that will start to break up around 4 with a PAF-style humbucker. If you would prefer that to happen at around 7 then an 12AT7 might be the trick.