A PET bottle ... a driven spool rolls it up. The spool of tape is then moved to the second stage of the machine, which pulls the tape through a hot end very similar to that on a 3D printer.

PETFusion 2.0 is both a PET (polyethylene terephthalate) bottle recycler and a custom 3D printing filament maker, with the ability to even apply your own ink/pigments to the filaments you make ...