General Electric GE 6688 Vacuum Tube Valve NOS-Testing RCA RC2 new in box US-made 6KU8

new in box US-made 6KU8 tubes tested to spec on our Paul Hart-calibrated TV7/U

excised chevrons in their top mica spacers as well as 210 5439 and 5413 provenance/date codes

great flashing

These four GE 6X8A tubes tested to spec on our Paul Hart-calibrated TV7/U

I am playing them as I write in my Alan Eaton single-ended 45 amplifier with RCA Living Stereo's CD of Bartok's "Concerto For Orchestra

General Electric GE 6688 Vacuum Tube Valve NOS-Testing RCA RC2 new in box US-made 6KU8This GE 6688 tube tested 110% on our Jackson 648 Mutual Conductance tester. BECAUSE OF THE BIZARRE, INTRUSIVE AND DRACONONIAN PACKAGING REGULATIONS AND THE SEVERE FINES AND PRIVACY INTRUSIONS ASSOCIATED WITH THEM WE WILL NO LONGER SHIP TO GERMAN ADDRESSES FROM JUNE 1, 2022. WE WILL HAPPILY SEND YOUR PACKAGE TO A NEIGHBORING COUNTRY OR MAKE SUITABLE ARRANGEMENTS. IN 2021 WE PURCHASED 150,000 VACUUM TUBES. IF IT'S NOT LISTED, WE PROBABLY HAVE IT. PLEASE