Saint-Gobain M797 polyester films have excellent dimensional stability, high tensile, tear and impact strengths and ultimate elongation up to 120% of its original dimensions. These films exhibit low water absorption and good resistance to oils, greases, strong acids and organic solvents. - Resists high temperatures of conformal coating operation, is silicone free, and creates a true masking line. They also retain electrical properties, dielectric strength and dielectric constant in continuous operating temperatures from -18 to 163 °C.