McIntosh MC275 spare tube set, ALL tubes sounding the same and tested on a calibrated Hickok 539c tube tester (Left to Right):

10,000 uMho's @ 106 mA plate current
10,750 uMho's @ 108 mA plate current
11,250 uMho's @ 112 mA plate current
11,250 uMho's @ 112 mA plate current

100% original, matched pairs, close to New Old Stock or very strong. No shorts or leakage; Hickok 60% minimum is 6,250 uMho's (Gm), therefore these KT88's test 90 to 100% new. Of note, one KT88 is a yellow lettering version (s/n 8448Z) and had its broken guide pin repaired. A fixing adaptor is included just in case it happens again.
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Also, included: (4) 12AT7's & (3) smooth plate 12AX7's. ALL testing strong (at least 90% new), quiet, and balanced. ALL Telefunkens!
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Finally, ALL tubes come within a very handsome McIntosh walnut wood box and original shipping box with matching serial number JS1912. This doesn't get any better than this, so don't let it get away!

Price $1295