It self dispenses automatically A modified spool holder to go beyond the basics. simply insert a spool & insert the filament right through the hole & then it self dispenses Preventing filament from unraveling or tangling Especially with a direct feed extruder & you can also add foam to have a dust filter for your filament and Its additionally useful for 3DPrinters where a alternative spool holder would be more convenient for spools up to around the size of a kg of filament