Abstract: A soft and flexible thin heating element is made of strong, light and non-metallic yarns. The heating element comprises electrically conductive carbon/graphite containing fibers, woven or stranded into the strips, ropes, sleeves or strands of threads. The selected areas of the heating element core are modified to impart additional electrical properties. An optional positive temperature coefficient (PTC) material is incorporated into said selected areas. The electrode conductors are attached to said heating element core which is electrically connected in parallel or in series. The heating element core is shaped in a desired pattern. The whole assembly is sealed by at least one electrically insulating layer which envelops the strips, ropes, sleeves, or strands of threads.