PETG filament is a close cousin to PET (Polyethylene terephthalate) filament. PETG is a new updated version that has enhanced properties. The optimum print temperature is between 215°C - 235°C. Please note that different printers print at slightly different temperatures. PETG filament has minimal shrinkage and warping. The filament has easy adhesion, so it can be printed on acrylic, glass, polyimide (Kapton) tape, blue tape, and others. A heated bed is not required.