Abstract: A plastic jacketed cable; having a corrugated metallic shield which encloses a core comprising a plurality of insulated conductors, for use in underground ducts exposed to elevated temperatures includes an inner jacket which is capable of providing and maintaining adequate strength properties notwithstanding imprinting thereof by the corrugations of the shield contiguous thereto, and an outer jacket superimposed over the inner jacket and suitable for resisting degradation while being exposed to the elevated temperatures for sustained periods of time.