I just hit the motherlode yesterday, getting a Zone VI Tachihara 4x5 field camera, two Schneider lenses, two light meters, about fifteen film holders, two lens hoods, dark cloth, assorted glass and Kodak Wratten gelatin filters, lens wrench, Ambico The Shade+ filter holder, self-timer attachment, bubble level, white padded soft case, hard aluminum case, and more, for $600. Outrageous. I had to strike while the credit card was hot.
Anyway, much of this stuff was obviously part of a kit obtained from Zone VI, including this little doohicky. It is a black-painted wooden square, about 1/4" thick and roughly about 2-1/2" square, with an amber- or orange-colored glass filter mounted in the middle, much like a slide. A hole is punched in the corner and a faux-leather thong is threaded through it, presumably for hanging around the neck. A Zone VI logo label was affixed near the opposite corner.
What is this thing? I'll post a picture if there are no obvious guesses. Thanks!