Cable shield
A cable shield is the conductive sleeve of a cable or lead and protects the conductor inside from being exposed to external electromagnetic fields, while preventing electromagnetic radiation emanating from the signals carried by the conductor from escaping into the environment.
Cable shields are typically made from thin copper wire that is braided or stranded and can be enhanced with foil. They are protected by an insulating, corrosion-resistant, and water-tight jacket and are used for shielded cables.