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

(1) Tested GE 5X8 Tube with Box Date Code FV General Electric Triode Pentode

(1) Tested Strong Sylvania 6JC8 Tube with Box Date Code NR ECW Triode Pentode

(1) Tested 1960 Sylvania 5X8 Tube Date Code GL ELM Triode Pentode Converter Tube

(1) Tested Sylvania 12JN8 Tube with Box Date Code NR AAA Triode Pentode Tube (b)

(1) Tested Sylvania 6JT8 Tube with Box Date Code bk Sylvania 6JT8 Triode Pentode

(1) Tested Sylvania 12JN8 Tube with Box Date Code YAA Triode Pentode Tube (a)

(1) Tested Sylvania 6JC8 Tube with Box Date Code NR EDF Triode Pentode Tube