[Milsurplus] whassa MX-991/U?

[little e]

de N4TGC Eric

	I have this dingus on my desk I've been meaning to ask about:
designated on the side "MX-991/U" it's about eight inches long, cylindrical
green plastic, with a peculiar, Fresnel-like lens at right angles to one
end, a slide switch on the side, and a un-screwable cap on the other end. I
discovered if I put two D cells in the internal hollow, I can produce a
rather weak light out of the lens.
	Question is, what is this thing, and does it serve any useful purpose?

	While I'm at it, what does antenna AT-5001/PRC fit? I have one that
appears to be defective: instead of the expected bungee cord thru the
sections, it has a stainless-steel 'aircraft' cable threaded thru it, and
no spring. Needless to say, it don't work right - I took it apart, and
think I can fix it, but what was the original construction? Can anybody use
it as is, or is it worth fixin'?
	e