(1) Tested RCA 6CF6 Tube RCA Sharp Cutoff Pentode Tube

6BD6 CBS Remote-Cutoff Pentode Vacuum Tube NOS - TESTED

6BC5 CBS Sharp-Cutoff Pentode Amplifier Vacuum Tube NOS - TESTED

5CG8 RCA Medium-Mu Triode Sharp-Cutoff Pentode Vacuum Tube - NOS - TESTED

6DE6 Westinghouse Sharp-Cutoff Pentode Vacuum Tube - NOS - TESTED

6CB6A GE Sharp-Cutoff Pentode Vacuum Tube - NOS - TESTED

6AG5 RCA Sharp-Cutoff Pentode Vacuum Tube - NOS - TESTED

Vacuum Tube, 6HS6, GE, Sharp Cut-OFF Pentode, Tested Hickok 539C