This is a holder for spools of Kanthal or whatever wire fits in them. They were designed around the spools that I have that were getting all like spools of wire do when they don't have a good way to keep them contained. THis keeps the wire contained in the spool while providing an opening to draw off the wire from and posts for tying it off to avoid that pointy end of wire sticking out.
Simply thread the wire through the hole provided, pop the spool onto the stud and then tie the wire off on the posts. To dispense wire, simply untie the wire, draw off the length needed, tie it off and cut.
The photos show the original version which did not have the stacking features in the presented files here.