(!!!!) (Best Pair) 6U8A=6678 GE NOS 1968 same date codes (14.0/14.2ma and 12.2/12.8ma) 1-3% matched
(!!!!) (Best Sylvania Pair) 6U8A Sylvania NOS 1970 era (17.0/16.4ma and 10.2/10.4ma)
(!!) (Recommended Single) 6U8A GE NOS 1977 (14.2ma/10ma)
(!!) 6U8=ECF82 Tungsram Hungary rebranded Haltron NOS 1970's (14.3ma and 7.6ma)
(!!) (Best Telefunken) ECF82=6U8 Telefunken Germany <> bottom NOS 1968 (13ma triode and 9.6ma pentode)
(!) ECF82=6U8 Telefunken <> bottom used/good 1967 (13.4ma triode and 6ma pentode)
(Best Value) 6U8A Rogers Canada NOS 1974 (14.8ma triode and 8ma pentode)
(!!!!) (Oldest Pair) 6U8A GE NOS 1962 (19.2/16.8ma and 11.8/10.5ma) (Close Gm)
(!!) (Recommended Single) 6U8A GE Amperex NOS 1974 (13.5ma/10.2ma)
(!!!!) (Recommended Pair) 6U8A Philips by Sylvania NOS 1986 (17.2/17.6ma and 8.4/8.6ma)
6678=6U8A GE NOS (3 in stock)
6U8A used/good
6U8A=6678 Dumont NOS 1971 (19.7/7ma)
7687 Sylvania NOS 1962 (sold out)
(!) (BEST SINGLE) 6U8A Sylvania NOS 1970 era (20ma/17ma)
(!!!) 6U8A Raytheon black plates NOS "U" getter halo 1962 (17ma and 8ma)
(!!) (Best Telefunken) ECF82=6U8 Telefunken Germany <> bottom NOS 1969 (24ma triode and 9.4ma pentode)
(!!) ECF82=6U8 Telefunken Germany <> bottom NOS 1968-1969 faded printing (14ma triode and 8.6ma pentode)
(!!!!) (Recommended Pair) 6U8A GE NOS 1973-1976 (19/18.8ma and 10/9.8ma)
(!!!!) (Recommended Pair) 6U8A GE NOS 1974-1977 (17.2/17.8ma and 8.6/8.4ma) 1-3% matched
