(!!!!) (BEST PAIR) 6DN7 GE branded GE and CBS NOS 1959 same build (46.4/46.5ma and 8/9ma)
(!!!!) (Best Pair) 6DN7 RCA NOS 1960's (30ma/9.6ma and 34ma/8.5ma)
(!!!) (BEST PAIR) 6DN7 GE branded Tungsol and RCA NOS black plate/gray plate 1960 era (40ma and 8.5ma and 40ma 7.7ma)
(!!!) (PAIR) 6DN7 Philco and Tungsol by GE NOS 1960's (33ma/9.2ma and 38ma/7.5ma)
(!!) (BEST SINGLE) 6DN7 GE branded RCA NOS 1960's (64ma and 7.2ma)
(BEST SINGLE) 6DN7 RCA NOS 1968 (38ma and 10.2ma)
(Best Single) 6DN7 Sylvania NOS 1960's (60ma/8.3ma)
6DN7 GE branded RCA NOS 1962 (46.6ma and 8.2ma)
6DN7 RCA Mexco coin-base same internals as Sylvania NOS 1970's (40ma and 8.5ma)
6DN7 Sylvania NOS 1970 era (39ma and 7.5ma)