I would say this is a remix of this model, but I redesigned it from the ground (no pun intended...?) up in FreeCAD. I did this in part to learn how to model, as well as I couldn't figure out how to do a clean remix using the STL from the model.

This is just a cap to fit (rather snugly) on my camping hand mill from Japan.

Printed with 15% infill (which is probably overkill), and no brim. Creality Black PLA.