(1) Tested RCA 6CX8 Tube with Box Date Code CR Medium Mu Triode Pentode Tube

(1) Tested GE 6EB8 Tube Date Code JU 6GN8 High Mu Triode Pentode Tube

(1) Tested Cornell 6EB8 Tube Date Code XRMT-PNH 6GN8 High Mu Triode Pentode Tube

(1) Tested RCA 6AW8 Tube with Box Date Code BKP 6AW8 High Mu Triode Pentode

(1) Tested Strong RCA 8GN8 Tube with Box Date Code AV Triode Pentode Tube

(1) Tested RCA 6AZ8 Tube with Box Date Code KG Medium Mu Triode Cutoff Pentode

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

(1) Tested RCA 5BR8 Tube with Box Date Code AQ Medium Mu Triode Cutoff Pentode