TAD 12AY7/6072A Highgrade Premium Selected and matched pair. Vintage tone for original vintage Fender tweed amps. The original tube for all those Fender tweed amps from the '50s. Brings back the original sound to your tweed amp. Matching in Pairs for preamp tubes means that two tubes show identical gain, hence, four characteristically identical systems. This matching method includes our Balance-Selection. We highly recommend this matching method for hi-fi systems.