(!) (BEST PAIR) 6CA4 RCA NOS 1960's - 1972 (54-56/40 and 54-54/40) (Wright, Counterpoint, Cary, Zanden)
(!) (BEST PAIR) 6CA4=EZ81 Sylvania NOS 1960's (53-54/40 and 52-53/40)
(!) (BEST SINGLE) 6CA4 Sylvania NOS 1960's (55/40 and 55/40)
6CA4 GE branded Tungsol like new 1960's (55/40 and 56/40)
6CA4 Philco by Sylvania NOS 1960's (52/40 and 52/40)
6CA4 RCA branded Super Airline NOS 1960 era (54/40 and 54/40)
6CA4 RCA NOS 1961-1962 (50/40 and 50/40)
6CA4 Silvertone by Sylvania NOS 1960 era (54/40 and 54/40)
6CA4 Sylvania NOS 1960 era (54/40 and 54/40)
6CA4 Tungsol branded RAD TEL NOS 1961 (52/40 and 52/40)
6CA4=EZ81 RCA used/good 1962 (53/40 and 53/40)
6CA4=EZ81 Sylvania used/good 1960's (53/40 and 53/40)