That title has an air of clickbait to it, and perhaps a touch of horror, but it actually fits somewhat. You see, I seem to have discovered a gaping hole in all the Trek tech geekery, and it's flashlights (or torches, for some of you, which is why I couldn't just name the thread "flashlights" or "torches").
I mean, I've seen little tidbits here and there about Trek flashlights, mostly the TNG stuff, but I literally can't find *anything* about the TOS flashlight from "Tomorrow is Yesterday"[TOS1].
Even on super prop sites that can track when a communicator prop got damaged when Takei grabbed it without its consent, there's zip-zilch-zero. Of course, part of this is that it's relatively uninteresting compared to other props.
As for the light itself, it had no apparent controls, though there are two red lines that appear to be three-dimensional linear structures along the peripheral lens covering, rather than mere paint. The faked beamshot using a spotlight or similar is well-done. The design is somewhat dull . . . it's basically a smaller version of LaSalle's signalling device from "Squire of Gothos" (a.k.a. Kirk's viewscreen fix-o-matic from "The Doomsday Machine), but without the spiky stepped clear part and instead with what may as well be a clear version of a modern soda bottlecap on top. Underneath that is what appears to be an aspheric (convex) lens, assuming it's not pointy at the top.
Kirk and Sulu aren't exactly set up for stealth on this mission ... they wear regular uniforms and don't use a tricorder for anything ... so the fact that this design isn't super-stealthy with its bare-metal look and side-spilling bottlecap lens isn't really a big deal. Contrasted with the classic Orilux WW1 and WW2 flashlight's low-observability features, however, this light seems a tad odd.
As for the lack of apparent controls, perhaps the control system is akin to the "motion-controlled variable power level" on the MagLite XL200 tactical model in which you rotate the body of the light in your hand (e.g. with a wrist motion) to change brightness. But wouldn't that be silly, either on the MagLite or this?" you ask. Yes, yes it would.
Alternately, the red marks on the bottlecap section could be a rotating bezel of some kind, but this is not observed.
In any case, I find myself really wanting to do a webpage on the flashlights of Star Trek since, near as I can tell, no one has one . . . but oh god, do I even have that kind of time anymore?
Of course, the fact is, all I really want is the TNG "palm beacon" from "Yesterday's Enterprise", et al. Don't think I'm not trying to figure out how to make a real one.