This is a filament spool for a Aerb Printing Intelligent 3D Pen with LCD Screen, Black, 6.4x10.2x20 (available from Amazon).

I was taken with Starman63's original design, however, it didn't work for me - spool too large, spool sides too thin & "perforated" (the axle holes popped out like a postage stamp), mount was too weak, the single mount fixing wasn't the right size for this particular pen and wasn't robust enough, needed a wider offset to accommodate the power cable. It sounds like I'm slating Starman63's design but I'm not - the fundamental design is exactly what I'm looking for - so thanks for the inspiration Starman63!

All the four elements can be printed together, in a wunner, without supports. Print the mount & cap on their backs. Once you have the mount & cap made you can print as many spools as you want/need.

I've also uploaded the STP files so you can modify any of the elements using your own CAD or design software.

Good luck, and let me know how you get on.

Eric