Matched Pair Western Electric 403B/5591 Square Getter Black Plate in Original Boxes Made in USA Same Date Code: 6013 Both tubes are made in 1960 in USA. Fully tested by calibrated Hickok 539C tubes tester with no shorts, leakage or gas. Measurement: 4500 4500 where minimum good value is 3150 Tightly matched pair! I will gladly combine shipping upon request.
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