This is the all new magnetic filament spool holder for rolls of filament 1 KG or less. Simply buy these https://www.amazon.com/gp/aw/d/B0C7M4LSBJ?psc=1&ref=ppx_pop_mob_b_asin_image magnets, print the hook, place the magnets in with some very strong glue, and voila! You have created a super cool filament storage solution for your locker or metal cabinet. This holds most 1kg spools. The only spools that I know don’t fit are inland cardboard spools. As seen in the images, it can hold smaller spools as well. I printed this on the TOYBOX with PLA with a very sparse infill and it works fine. TOYBOX doesn’t let you change settings like infill because it is targeted towards a younger audience. I recommend a more dense infill. Also, please use supports!