This tube is for extend the stock Creality spool holder and permit to mount multiple spools.
Print in PLA is good, ABS is better.
Put the internal screw side bottom and print with 5-10 brim lines.
Print more tubes and connect them for create a modular support.
After printed, screw and unscrew some times for screws adaptation.
Screw and unscrew some times for optimal screws adaptation.