(1) Tested National Union 12AL5 Tube with Box Date Code 5152 Double Diode Tube

(1) Tested Sylvania 12BR7 Tube with Box Date Code bf JEK Twin Diode Triode Tube

(1) Tested Strong RCA 12H6 Tube with Cleaver Brooks Box Date Code DE Diode (c)

(1) Tested GE 12AT6 Tube with Box Code DE General Electric Twin Diode Triode

(1) Tested Sylvania 3AV6 Tube with Box Date Code ACG Twin Diode High Mu Triode

(1) Tested Sylvania 6BJ8 Tube with Box Date Code ER DHL Twin Diode Triode

(1) Tested Sylvania 6BJ8 Tube with Box Date Code NR KAB Canada Twin Diode Triode

(1) Tested RCA 12EM6 Tube with Box Date Code LR Diode Tetrode Tube