The S5 (when it works as an S5 Pro Bundle) has the peculiarity of extruding into the workroom when a print is started. With a material station connected, it does this more intensively. The filament threads then collect in the workroom and are difficult to remove. The bin catches these filament threads. The bin is removable attached to the bottom and sides of the print room with Velcro tape. The dimensions of the bin are optimised for this purpose. There is a little video about the bins https://www.youtube.com/watch?v=p6QOAR57o28 Have fun with it