When we need one laminated bag, how should we choose the material of the bags' surface ? Advantages of PET - Greater strength resulting in better control for repeat length and slitting size. - Higher heat resistance (~250°C) making it the preferred choice for fast speed packing machines (OPP can only withstand up to 180°C) - Stronger bonding wit ink and PE resin. Disadvantages of PET - Higher cost in comparison to OPP