PET films are characterized above all by high tensile strength, chemical, mechanical and thermal stability, and transparency. They are a good electrical insulator and have a low water absorption (0.3%), as well as an electrical breakdown strength of about 133 V / µm.

Standard strengths are:
23 µm
36 µm
50 µm
100 µm
150 µm
190 µm
250 µm
300 µm
350 µm
500 µm

It is also possible to combine individual layers of the material into one Laminate to glue in order to achieve greater strengths.

Best known brands are Mylar A von Dupont as well Hostaphan von Mitsubishi.