Tri lobe nut spinner.

Initially designed for use with featherboards/fingerboards 4724631 and 4728676
https://www.thingiverse.com/thing:4724631
https://www.thingiverse.com/thing:4728676

But could be used on other projects so deserves a place of its own.

The first version is designed with a clearance hole for 8mm threads.
The hex hole is designed for 13mm across flats (A/F) nut to fit into.

The second version had a 8mm thread imbedded into the design.
Depending upon your print quality, it may require a clean up of thread form using an 8mm x 1.25mm metric (coarse) tap.
It should also be possible to drill clearance hole if necessary in this design if printed with suitable wall thickness.

Creality

CR-10

I printed upside down,
ie the larger face on the print bed.
without supports, which gave rise to a less than perfect "nut face", it didn't have a smooth finish but since there will be a nut in the slot, the face will be hidden.
Some adhesive in here may help retain the nut, when it is removed from the bolt/threaded bar.