(!!!) (Best RCA Pair) 6DR7 RCA NOS 1975 (1.5/34ma and 1.6/42ma)
(!!) (PAIR) 6DR7 Sylvania and Sylvania branded Raytheon black plates NOS 1970 era (1.4ma/37ma and 2.0/33ma)
6DR7 GE black plates NOS 1963 (1.5ma/57ma)
6DR7 GE branded Philco black plates NOS 1969 (2.0ma/38ma)
6DR7 GE NOS 1965 (1.1ma/36ma)
6DR7 Raytheon black plates NOS around 1960 (1.2ma/40ma)
6DR7 RCA Rauland NOS 1961 (1.7ma/50ma)
6DR7 Sylvania branded GE black plates NOS 1977 (4.6ma/25ma)
