(1) Tested Philco 6BC5 Tube Date Code 5311 Sharp Cutoff Pentode Tube

(1) Tested Zytron 6BC5 Tube with Box Date Code 56-20 Sharp Cutoff Pentode Tube

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

(1) Tested Philco 6AU6 Tube Date Code 247 Philco 6AU6 Sharp Cut Off Pentode

(1) Tested Truetone 6BC5 Tube with Box Date Code 6517 Sharp Cutoff Pentode Tube

(1) Tested National Union 6BC5 Tube Date Code 533 Sharp Cutoff Pentode Tube

(1) Tested RCA 6HS8 Tube with Box Date Code AR Sharp Cutoff Twin Pentode Tube

(1) Tested RCA 6AG5 Tube Date Code LS RCA Sharp Cutoff Pentode Tube