Tight buffered fibres are surrounded with a layer of aramid yarns as the strength member. A LSZH inner sheath is extruded on the tight buffered fibre to form an optical sub-unit. Then optical sub-units and copper wires are stranded around a non-metallic central strength member to form a cable core. The core is armored with laminated aluminum tape. Finally, a LSZH outer sheath is extruded. Other sheath materials are available on request.