From my personal collection. I purchased a tray of these many moons ago, military USAF surplus. Absolutely outstanding tubes, with a musical texture that can be downright mesmerizing. Deep bass, top end sparkle, IMO there is really nothing that beats them. These have the shiney 2 hole high T plates with early 50's bottom foil getter. They are true NOS tubes, and test as new. Glass is mint with no heat venting over plates. I suggest you get them as NOS while you still can. In this tray, some had markings, some did not. I learned that at times, in military bulk, as a way to save on cost, tubes were not labelled. I will sell 2 pairs at $350/pair, and price is firm. PayPal and tracked shipping included to lower 48 states.
All tubes are tested on 2 different and very accurate mutual conductance testers with no bloated or just plain made up results, with tubes especially, do not lose sight of the fact that most often, you get what you pay for. Tubes will be packed tightly and safely; look to my other classifieds for other fine vintage tubes, and be sure to drop me an email with any questions, or inventory needs, thanks