The basic material PET (polyethylene terephthalate) is generally known and very widespread in almost all sectors. For 3D printing, however, the sub-material PETG is usually used. The G stands for "glycol-modified". This modification makes the material clearer, more stable and last but not least easier to print. With regard to its stability, PETG lies between ABS (even more stable) and PLA (less stable). PETG scores points above all for its flexibility, strength, temperature resistance and resilience. On the one hand, it is suitable for visually attractive visible components and on the other hand for components subject to mechanical stress. PETG is used for functional prototypes as well as for coarser threads within components.