(!!) (Best Pair) 6CS7 Sylvania NOS (1) RCA "U" getter (1) Philco "O" getter 1960 era (23/11ma and 23/11ma)

1 pair) 6CS7 Sylvania NOS (1) RCA "U" getter (1) Philco "O" getter 1960 era

1 tube) 23ma Gm=4800 and 11ma Gm=2300 branded RCA "U" getter (LQ) 1960 

1 tube) 23ma Gm=4500 and 11ma Gm=2300 branded Philco "O" getter 1960 era 

for:

Leben CS 600 integrated amp
Leben CS 660P power amp