Set of 4 General Electric 6SN7GTB twin triode vacuum tubes-used. Each tube tests strong and each has a close cross section match. Test results 3150/3050, 2730/2800, 2490/2450, and 2940/2800 uMhos with a baseline 1750 uMhos acceptable. Tested on Hickok AN/USM-118B tube tester. Will be packaged in white tube boxes.