Uses 608 size bearings. I had some 8mm tubing with a metal rod shoved in it to keep it straight, so you will need some kind of 8mm shafts. The spacer piece is set to the length for Hatchbox brand spools, not sure if it will work with others.
I also included the cut jig for Sterilite containers https://www.amazon.com/gp/product/B00H1PS2TS/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
The quick swap filament clip thing in the front of the pictures is here: https://www.printables.com/model/373113-quick-swap-top-load-filament-handler
The author marked this model as their own original creation.