Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:4973098. This spool holder is to bridge the gap between the bearings ASX1 spool holder. So you don't have to fiddle with a bolt when you change filament and lets you quick change. This is a common complaint and this is my solution. if you have the Inventor file plugin in Cura it opens cleaner and you can get a smoother surface.