In fact, I was getting a little fed up with having to fish out residue from the bottom of the extrusions of my Eryone Thinker X400, so I set about taking measurements and designing covers to insert into the extrusions,. Of course I could use some rubber extrusion covers, but I wanted them to fit the color of the Thinker X400 printed parts, so I decided to design them in order to be able to print them with some orange Eryone PETG.