A Lead Sheath is available on many types of wire and cable insulations. This sheath is completely moisture proof and very durable. Where both mechanical strength and moisture resistance are required, a combination of Lead sheath and armor can be used. Underground ducts and wet locations are typical areas where Lead-sheathed cables are used.

Lead has the major advantage that it can be applied to the cable core in unlimited lengths by extrusion at temperatures which do not damage even the most sensitive conductors (optical fibers) or insulating materials (paper or plastics). Lead is pliable and so can withstand the several coiling, uncoiling, handling and bending operations involved during the later manufacturing stages and installation of the cable. A Lead sheath can be readily soldered (again at low temperatures) when cable lengths need to be jointed or new cables installed. With modern screw-type continuous extruders, un jointed lengths of submarine power cables as long as 100 kilometers have been produced.