Fidgeting ring to calm your nerves. This is a print-in-place two piece ring with very close tolerances. This will require a well tuned / calibrated printer with 0.4mm nozzle to successfully print this properly. The ring is size 12 US.

Keep in mind this is a 3D printed part and not a machined part, it will not spin like it has bearings. :D

Print instructions

0.4mm nozzle
0.12mm layer and initial layer height
2mm shell
no support needed
ABS or PLA
Z-offset must be well calibrated to prevent elephant foot effect of the first layer. May require the use of a craft knife to very carefully separate the first layer if they're stuck together. Once the outer and inner ring are separated, keep rotating the rings to help smooth out the inner surfaces and the spinning performance with increase with use.