(!!) USN-5687WA Tungsol black plates "U" getter used/good 1956 (27.5/28.5ma)
$ 39.99
1 low noise tube) USN-5687WA Tungsol black plates "U" getter used/good in white boxes 1956
27.5ma Gm=10,000
28.5ma Gm=10,200
Tested on Amplitrex
Good used Ma range 25-30
Good used Gm range 9000-11,000
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