This is a cap for the screw hole in the Sideplate print for Captain Slug's FLAK nerf rifle.
I did a bit of sanding to make the cap sit flush (and help the stain take), then added a touch of superglue and pressed the cap into the side plate. Note that the fit was tight enough without superglue that I had to pry the cap out with tweezers. I'd recommend removing the U channel before doing that.
Printed using SUNLU Wood PLA on a 0.4mm nozzle at 0.15mm layer height. I used a brim for bed adhesion, and the print took under 10 minutes.
The author hasn't provided the model origin yet.