The plastic tube designed to insert into the channels of the frame of the Creality CR 10 series of 3d printers are functional. Yes, you can choose from 3 colors, orange, black, or blue, but the function is what it is all about. These open channels on the extrusions will collect all manner of plastic, dirt, and dust. The plastic tubes will prevent that from happening! Just cut to fit and insert the tubes into the channels, and your printer will stay much cleaner.