1x NOS Gold Aero 7581A KT66 OE PowerTube by GE USA ~ 6L6GC EL37 6505/5150 Head
Full mutual conductance gm test + leak/short/gas and life checks (longetivity), pristine set over 100 % gm (65). highly revered for their sound reproduction, these top echelon usa classics are often described as an open clear tonality.