as spool knitting devices for making gloves (though the earliest known reference to spool knitting is from 1535, and this would neither explain the use of bronze, nor the apparently similar icosahedron which is missing the holes necessary for spool knitting)
It looks like you would wrap fibers around the vertices to make something 3d out of frabric tbh.
Edit: it seems my theory has been largely discounted 😔
I remember speculation that this could have been used to make gloves. That was discounted?
From the wikipedia
Not entirely discounted but considered unlikely