PETG is the most commonly used form of PET (polyethylene terephthalate), with the G version being a glycol modified PET, which is a widely used engineering thermoplastic. PETG has strong, durable properties and good heat resistance like ABS, but is easier to print. Parts printed with PETG are used not only in the prototype stage of product development, but also in later stages of functional testing and part assembly. Printed PETG parts have been used successfully in manufacturing applications with or without post-processing.