Yes, with watches it does get very complicated. With the advent of ebay in particular, the term NOS for tubes gets somewhat complicated as well. Some sellers seem to believe it is okay to call a vacuum tube NOS as long as it is in its original box. It's a bit harder to determine whether such a tube is actually NOS. You can test it on a tube tester to see if it meets minimum parameters but it still might be "slightly used" and still exceed minimums. They might even be "pulls', tubes that have been pulled out of used equipment and put back into an appropriate box because they still test "ok". Output and rectifier tubes have very visible mirroring on the glass envelope behind which sits a "getter" which burns off excess, stray gas/impurities when a tube has power applied to it. The longer a tube is used, the more the mirroring (silver looking) begins to fade to an off color, usually brown. This can help you make a judgement call on their amount of use. But, some tubes with a few months use on them may still show little of that effect making it easy to pass them off as NOS. You never really know unless you buy from the individuals who originally purchased the tube(s) from the manufacturer. That's why for many years, starting about 1988, early in the morning (before my day job appointments) I scoured wholesale electronic supply houses when on business trips for new tubes applicable to my gear since those tubes came from known sources, usually directly from the manufacturer or, their authorized distributor. These supply houses used to be in every state, many with multiple locations. Unfortunately, nearly all of those "jobbers" are now gone. Victims of "throw away" non-repairable electronics now being made today. Government auctions of surplus tubes were also a good source of quality, tested, fully vetted military graded vacuum tubes. These are generally in white boxes and labeled "JAN" (Joint Army/Navy) along with month/year of manufacture and other data imprinted on the tube boxes. The winning buyers of those auctioned tubes tended to be large tube purveyors, though, not an individual like me. As you have often taught us watch guys, it pays to buy the seller, not the watch (or tubes)!

Steve

: Interesting that vacuum tubes are the example that is often used
: in the discussion of "new old stock"; here's the
: Wikipedia entry -- https://en.wikipedia.org/wiki/New_old_stock

: Vacuum tubes are an interesting example. I imagine that when
: electricity flows through one of these tubes, all can agree that
: the tube is no longer "new".

: I am accustomed to seeing the term used in connection with car
: parts. I had a 1971 de Tomaso Pantera, and there was a market
: for NOS parts for the engine, interior, etc. Once again, when a
: particular part went out of the box and into the car, it was
: clear that the part was no longer "new". All agreed on
: that.

: With watches, it gets a bit more complicated, doesn't it?

: Jeff

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