(1) Tested RCA 6CX8 Tube with Box Date Code DM Medium Mu Triode Pentode Tube

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

(1) Tested RCA 6CX8 Tube with Box Date Code NF Medium Mu Triode Pentode Tube

(1) Tested Philco 6JE8 Tube Date Code EBF High Mu Triode Sharp Cutoff Pentode

(1) Tested Sharp Japan 17JZ8 Tube Date Code 8-7 Medium Mu Triode Power Pentode

(1) Tested Rad-Tel 6X8 Tube Date Code 5-66 6X8 Triode Pentode Converter Tube

(1) Tested GE 6EB8 Tube Date Code JU 6GN8 High Mu Triode Pentode Tube

(1) Tested RCA 6CX8 Tube with Box Date Code CR Medium Mu Triode Pentode Tube