The outer layer or sheath is also made from PVC, offering additional mechanical protection to the internal conductors. It helps prevent physical damage, exposure to moisture, and environmental stress.
PVC sheathing also provides fire resistance, preventing flames from spreading in case of a short circuit or overheating.
These cables are specifically designed to be highly flexible, which makes them ideal for use in situations where the cable needs to bend, twist, or move (e.g., in machinery, tools, or power cords). The flexibility comes from the construction of the cable, where smaller strands of copper or aluminum are used for the conductor.