(1) Tested Silvertone 6BC5 Tube Date Code 312 Sharp Cutoff Pentode Tube

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

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

(1) Tested 1956 GE 6BC5 Tube with Box Date Code 56-52 Sharp Cutoff Pentode Tube

(1) Tested Philco 6AU6 Tube Date Code 55-47 Philco 6AU6 Sharp Cut Off Pentode

(1) Tested Sylvania 6EW6 Tube Date Code 548 Sharp Cutoff Pentode Tube

(1) Tested RCA 3CE5 Tube with Box Date Code MI Sharp Cutoff Pentode Tube (b)

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