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

(1) Tested RCA 6AU6 Tube Code GR Sharp Cut Off Pentode Vintage Tube

(1) Tested RCA 6AU6 Tube RCA Sharp Cut Off Pentode Vintage Tube (b)

(1) Tested RCA 6AU6 Tube RCA Sharp Cut Off Pentode Vintage Tube (c)

(1) Tested RCA 6AU6 Tube Date Code 504 RCA 6AU6 Sharp Cut Off Pentode Tube

(1) Tested RCA 6AU6 Tube RCA Sharp Cut Off Pentode Vintage Tube (a)

(1) Tested Admiral 6AU6 Tube Date Code 939 6AU6 Sharp Cut Off Pentode

(1) Tested Philco 6AU6 Tube Date Code 3031 Philco 6AU6 Sharp Cut Off Pentode