Slapped this little box together with Tinkercad.
It's to hold extra blades for a plotter which often come in those small clam-shell type boxes and 2 blade holders themselves. I found that the hole for the larger holders ( the silver Graphtec style) had to be SLIGHTLY reamed out (not much) for them to drop down and sit on the smaller ledge to prevent any blades left in wouldn't touch the bottom of the box and possibly throwing off any 'precise' adjustments for the blade itself. The older Roland type holder (bronze) slipped in without any problem. The top/lid for mine turned out fine and fits snug enough to not fall off and doesn't have to be snatched and jerked on to remove.