Offered is a pair of National Union 6SL7GT Twin Triode Tubes. One is a US Military Signal Corps type JAN-CNU-6SL7GT and (1) is a standard consumer grade 6SL7GT.  The tubes are clean and in good condition. Each tests good on the Jackson Dynamic Tester and they show no shorts or inter-element leakage.The tubes have robust triode readings-no feeble or weak tubes are included. These two have dark grey smoked glass interiors, black plates and lower getters with good silver flashing visible on both tubes. Production codes are as follows for the black bases: 244 and JC, codes on the glass below the designations read: NG and YT. Pick up these two for your own equipment for a nice upgrade. Mouse over the photo images to zoom in. NO RESERVE!! Thanks for looking.