(!!!) (#1 6BX7GT RCA single) 6BX7GT RCA NOS 1961 (41/48ma)
(!!!) (Best Single 1950's) 6BX7GT GE Zenith "D" getter halo NOS 1958 (74/70ma) (Highest mA and Gm)
(!!!) (Best Single 1953) 6BX7GT Philco by Sylvania "D" getter halo 1953 (56/63ma)
(!!!) (Best Single 1953) 6BX7GT Raytheon by GE "D" getter halo 1953 (58/68ma)
(!!!!) (Best GE Pair #2) 6BX7GT GE "O" getter gray plates 1960's (50/56ma and 53/59ma)
(!!!) (Recommended Single) 6BX7GT GE "O" getter gray plates 1963 (71/76ma)
(!!!) (Recommended Single) 6BX7GT GE branded Westinghouse "O" getter gray plates 1960's (43/48ma)
(!!!) (Recommended Single) 6BX7GT GE branded Westinghouse black plates NOS "O" getter 1962 (71/79ma)
(!!!) (Recommended Pair) 6BX7GT GE branded RCA NOS 1958 and 1963 (47ma/52ma and 45/50ma)
(!!!) (Recommended Pair) 6BX7GT GE branded Tungsol black plate "D" getter NOS 1957 (53ma/57ma and 48/53ma)
(!!) (Recommeded Pair) 6BX7GT GE branded NOS "D" getter 1958 - 1 tube branded RCA (72ma/95ma and 92/87ma) (highest mA and Gm)
(!!) 6BX7GT Sylvania "D" getter halo NOS 1950's (44/46ma) (close triode balance)
(!!) 6BX7GT Sylvania black plates NOS 1960's (56ma/76ma)
(!!) 6BX7GT Sylvania branded GE black plates 1967 (44ma/61ma)
(!!!) (Single) 6BX7GT GE branded RCA "D" getter halo NOS 1957 (70/55ma) (close Gm)
6BX7GT CBS NOS 1959 (53ma/73ma)
(!!!) (Best Pair) 6BX7GT GE "D" getter NOS 1954-1956 - 1 tube branded Raytheon (53ma/50ma and 47/52ma)