This is a filament roller that fits nicely on top of the IKEA Stuva Box. It can hold multiple spools at once (if you need).
I used a 1 meter aluminium tube, which I cut in half - change the length to your needs. To properly fit the provided adapter the tube should have 22mm inner and 25mm outer diameter. If you need different diameter, just write down in the comments, I'm happy to help out and providing you the adapted STL file.
Further I used 4x 624ZZ (4x13x5mm) bearings and appropriate axels.