Anycubic 4Max Pro Internal Spool

Print parts at last in PETG, or better in ABS - ASA. You will need 1x M3 10mm and 1x M3 8mm.
If you use this spool holder https://www.thingiverse.com/thing:2451368 you can put the spool into the chamber, using the heat of the chamber (about 50-55 degrees with the heated bed at 100) for spool preheat. It can be usefull with some materials that needs a preheat for better results.