Protects the internal construction from external influences. Here a temperature resistant (-60 °C ...+180 °C) silicon jacket protects the wires against short-circuits, especially during continuous use with high temperature differences. The non-dripping insulation is made of a silicon rubber and is resistant to oil, alcohol, fat as well as diluted acids, alkalids, oxygen, and ozone. The silicon jacket is very flexible and allows bending radii down to 15 mm (0.59 in.). The fine Cu wires are tin-plated and built according to VDE0295, class 5.