(1) Tested Zenith 10GN8 Tube High Mu Triode Sharp Cutoff Pentode Tube

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

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

(1) Tested Sylvania 6T8A Tube Date Code ab ESO Triple Diode High Mu Triode Tube

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

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

(1) Tested Zenith 6KT8 Tube High Mu Triode Sharp Cutoff Pentode Tube

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