(1) Tested GE 6AT8 Tube with Box Date Code 60-43 Triode Pentode Converter Tube

(1) Tested RCA 6BH8 Tube with Box Date Code BZ 6BH8 Triode Pentode Tube

(1) Tested RCA 5BR8 Tube with Box Date Code AQ Medium Mu Triode Cutoff Pentode

(1) Tested RCA 5AN8 Tube with Box Date Code KQ Triode Pentode Tube

(1) Tested RCA 6661 6BH6 Tube with Box Date Code 67-09 Triode Pentode Tube

(1) Tested GE 6JC8 Tube with Box Date Code SC General Electric Triode Pentode

(1) Tested RCA 6EB8 Tube Date Code AP High Mu Triode Pentode Tube

(1) Tested Philco 6AU8A Tube with Box Date Code 6504 Triode Pentode