(1) Tested RCA 6BK5 Tube with Box Date Code CL RCA 6BK5 Beam Power Tube (d)

(1) Tested RCA 6BK5 Tube with Box Date Code CL RCA 6BK5 Beam Power Tube (b)

(1) Tested RCA 12DB5 Tube with Box Date Code MI RCA Beam Power Tube

(1) Tested Very Strong RCA 6BK5 Tube with Box Date Code CL RCA 6BK5 Tube (c)

(1) Tested RCA 6BK5 Tube Date Code CL RCA 6BK5 Beam Power Tube (a)

(1) Tested RCA 6DT5 Tube with Box Date Code AL RCA 6DT5 Beam Power Tube

(1) Tested RCA 6DT5 Tube with Box Date Code DV Canada RCA Beam Power Tube (b)

(1) Tested Strong Hytron 6DT5 Tube with Box Date Code EFD NE Beam Power Tube (d)