 KT66 tubes continued to be manufactured at Reflektor Saratov in Russia, JJ Electronic in Slovakia, and at Liuzhou in China.Some modern Russian manufacture Sovtek KT66 tubes are actually 6L6GC tubes in a KT66 style bottle.While these tubes have the same pinout and minimum tolerances required of a KT66 tube, they do not have the performance characteristics of a true kinkless tetrode KT66 tube.