(1) Tested Strong RCA 9AU7 Tube with Box Date Code NF RCA 9AU7 Double Triode (b)

(1) Tested RCA 9AU7 Tube with Box Date Code BG RCA 9AU7 Double Triode Tube

(1) Tested RCA 6GH8A Tube with Box Date Code HE Triode Sharp Cutoff Pentode Tube

(1) Tested RCA 6BR8A Tube with Box Date Code CB RCA Triode Pentode Tube

(1) Tested RCA 12BR7 Tube with Box Date Code AV Twin Diode Triode Tube

(1) Tested Very Strong RCA 6GN8 Tube with Box Date Code DL High Mu Triode Tube

(1) Tested RCA 5X8 Tube with Box Date Code KP Triode Pentode Tube

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