This is an early 1950’s JG GE 12AT7 from military stock. Being made in the early 1950’s (1951-1953), these tubes are about as close as you can get to the origin of the most popular vacuum tube pinout on the planet. Keep in mind the 9-Pin miniature tube was developed in 1948. These specific tubes were early military orders and are of the highest quality available. The United States military relied on these for computers and targeting equipment. They *had* to work well. And they will work great in your gear. These all have the 1950’s era “D” style getter.
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