The US military had these JAN (JAN = Joint Army Navy) tubes made to special specifications for a stronger quieter output. 

Each tube fully tested and most are closely matched to one another in mutual conductance and current draw (please see pictures and test results). Auditioned in a p/p guitar amp and a single ended stereo and they sound wonderful with sweet vintage TONE!! Nice clean sounding vintage tubes with excellent detail and a very smooth base! All tubes are clean and look nice with little to no surface rust.

You can safely use these in any 6L6 OR 6V6 type amp that calls for 6L6, 6V6 tubes with no mods needed.

Tube Number       JAN CRC-6L6, VT-115

Actual mfr             RCA

Country of mfr      USA

Date codes           various

Plate style            BLACK

Test results (typical new = 5000 Gm, 45.0mA, 60mA (pp, se)

 *please see pictures for test results.

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