Come Check us out on Instagram or Twitter!! @3DPrintFresno Some filaments come with a larger interior cylinder than the FlashForge Creator's existing Filament spool posts, therefore these go onto the back of one side of the Creator's filament posts, if you have a dual extrusion model you will need to print two, for a total of four items. Place one spool spacer onto the post with wide end facing printer, next place filament roll on spacer, insert last spacer with wide end facing you, replace the tightening nut and you're good to go. Faster prints speeds, and lower infills are probably a good idea.