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

(1) Tested RCA 6AU8 Tube with Box Date Code KQ Triode Pentode Tube

(1) Tested Very Strong RCA 6BK4B Tube with Box Date Code CB Diode

(1) Tested Balanced RCA 9AU7 Tube and Box Code NF RCA 9AU7 Double Triode (a)

(1) Tested RCA 8CM7 Tube with Box Date Code NI RCA Double Triode Tube

(1) Tested Zenith 11CY7 Tube with Box Date Code 58-22 Double Triode Tube

(1) Tested Strong RCA 8GN8 Tube with Box Date Code AV Triode Pentode Tube

(1) Tested RCA 6GF7A Tube with Box Date Code CB RCA 6GF7 A Dual Triode Tube