A simple set of dividers held together by a printed screw, for measuring figure movements in inches in tabletop gaming.
I would advise printing on a filament printer for robustness. It's also worth noting the thread is on the loose side, to accommodate printers that are in need of a bit of calibration (like mine was at the time!) but it should hold quite firmly. If it doesn't, fiddle with your settings until it does!
The author hasn't provided the model origin yet.