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

(1) Tested Sylvania 10GN8 Tube Date Code 1F High Mu Triode Sharp Cutoff Pentode

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

(1) Tested Strong Philco 6BC5 Tube Date Code 61-47 Sharp Cutoff Pentode Tube

(1) Tested Cornell 6EB8 Tube Date Code XRMT-PNH 6GN8 High Mu Triode Pentode Tube

(1) Tested Meck 12AT6 Tube Date Code 8-22 GE EIA Code Twin Diode High Mu Triode

(1) Tested RCA 6JE8 Tube with Box Code AV High Mu Triode Sharp Cutoff Pentode

(1) Tested RCA 6AU8 Tube Medium Mu Triode Sharp Cut Off Pentode Tube