RCA 21LU8 Vacuum Tube Valve NOS NIB Matched Pair 6AU6 and dynamics even though these

and dynamics even though these amplifiers use 6J5s

These four RCA and Cunningham number / type 27 tubes tested as low goodand good on our Paul Hart-calibrated TV7/U

new in box Sylvania 10GK6 tubes tested to spec on our Paul Hart-calibrated TV7/U

The spine is in fine shape with no loose pages and APPEARS to be leather-bound

RCA 21LU8 Vacuum Tube Valve NOS NIB Matched Pair 6AU6 and dynamics even though theseThis new old stock, new in box RCA 21LU8 tube tested to spec on our Paul Hart calibrated TV7 U. WE HAVE SCORES OF THOUSANDS OF VACUUM TUBES. IF IT'S NOT LISTED, WE MAY HAVE IT. PLEASE ALSO SEE OUT ETSY SISTER SITE "LOWTECHTWOO" AND OR CALL OR TEXT US AT 202 372 6931 IF YOU DO NOT SEE WHAT YOU NEED OR HAVE ANY QUESTIONS. 1. MOST OF THE TUBES WE SELL ARE OVER 70 YEARS OLD. WE CANNOT GUARANTEE FOR FAILURES AFTER POWER UP AS THERE IS NO WAY TO DETERMINE