This is an armillary sphere ring, loosely modeled after https://www.britishmuseum.org/collection/object/H_AF-1760

These types of rings date back centuries and mimic the shape of armillary spheres, which were used to take exact measurements of astronomical observations. This is just a plain one with my maker's mark on the outer arms.

I highly recommend using PETG for this print, as PLA is far too brittle at this thinness. I'd also recommend a lot of patience, as even in PETG, I had to print quite a few before getting a workable model. Pay special attention to the holes in the arms when removing from the print bed/supports, as they are very thin and prone to breaking if too much force is applied. They're a bit more tough once assembled however, and I wear mine for light day-to-day use with little issue.

To assemble, align the small inner rings, then slide them over the pegs in the inside of the middle ring until they are seated. The middle ring can be pressed on either side a small amount to allow clearance. Do the same with the larger outer rings, but try to avoid pressing their sides for clearance, as they are more brittle.