6SN7GTBBranded HitachiRound TipBaseBlackBottle HeightHalfBottle ShapeSkinny BottleCountryJapanGlass ColorClear GlassMicaDoublePermanentidx72gkw430Pin ColorSilver PinsPlate ColorBlackTip ShapeRound TipMore 6SN7GTB type tubes6SN7GTBBranded Relco6SN7GTBBranded Hit-RayItt6SN7GTBBranded Sylvania6SN7GTBBranded RCA6SN7GTBBranded Sylvania6SN7GTBBranded Amperex6SN7GTBBranded Ge6SN7GTBBranded CEI6SN7GTBBranded PhilipsRogers6SN7GTBBranded RCAMore tubes branded Hitachi12AX7ABranded Hit-RayHitachi7591Branded Hitachi6CA7Branded Hitachi6CA7Branded Hitachi7591Branded Hitachi12AX7Branded Hitachi6CA7Branded Hitachi12AU7Branded Hitachi