A Wyse terminal:
Interesting for a couple of reasons.
One, not only does it come with the original box. But the original box is addressed to Thinking Machines. From where over 35 years it made it to a thrift store in Danbury.
Second, the keyboard, in all its stepped glory (all the contact surfaces are 1u, no matter what the size of the keycap), is one of those ones with the weird 10-pin connector. Yes, it looks kind of DIN-ish, but as far as I know isn't a standard. I have a similar keyboard from an OEM, Altos. The protocol is fairly well documented and there is a version of Soarer's for these, except everybody connects to it by taking off the cable and plugging into the 10-pin header directly.
There aren't any markings on the plug. If someone does get inspired to acquire the terminal (anything beyond a keyboard takes up too much space for me), I'd be interested to know whether the receptacle has any.