(1) Tested GE 6CU8 Tube and Box Code HF General Electric Triode Pentode Tube

(1) Tested GE 6CU8 Tube with Box Code EZ General Electric Triode Pentode (a)

(1) Tested GE 6CU8 Tube and Box Date Code EZ General Electric Triode Pentode (b)

(1) Tested Sylvania 6CU8 Tube with Box Date Code am YAD Triode Pentode Tube

(1) Tested Sylvania 6CU8 Tube with Box Date Code ce EEY Triode Pentode Tube

(1) Tested GE 6CU5 with Box Date Code LW General Electric Power Pentode Tube

(1) Tested GE 5GH8 Tube with Box Date Code JC General Electric Triode Pentode

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