(1) Tested Strong RCA 12H6 Tube with Cleaver Brooks Box Date Code DE Diode (a)

(1) Tested Strong RCA 12H6 Tube with Cleaver Brooks Box Date Code DE Diode (e)

(1) Tested Strong RCA 12H6 Tube with Cleaver Brooks Box Date Code DE Diode (b)

(1) Tested Strong RCA 12H6 Tube with Cleaver Brooks Box Date Code DE Diode (d)

(1) Tested Very Strong RCA 6BK4B Tube with Box Date Code CB Diode

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

(1) Tested RCA 6JU8A Tube with Box 6JU8 A Date Code HD Quadruple Diode Tube (c)

(1) Tested Strong Ken-Rad 12AT6 Tube Date Code 6-30 Twin Diode High Mu Triode