I was missing the hinge knobs on one of my 5 1/4 " Floppy Disk Box so I decided to try my hand at designing one. If I ever have to print more I would make them about 10% larger on the X and Y axis as the fit is a bit loose. I just used PLA for this model. Hope this model can help someone else however this is an excellent project to do from scratch if like me you are just learning CAD.