The present invention relates to an electric submarine power cable, in particular for use in hydrocarbon pipeline heating systems and adapted to be installed as a piggyback cable on said pipelines, comprising a multi-wire stranded conductive core with an outer insulation and at least one outer protective sheath as well as armouring means. In one aspect, the light source comprises a non-planar array of substantially straight tubes. The present invention also relates to various speaker systems which do not include speaker magnets but include various electric andor magnetic shields in addition to such drive and counter members. The wear bushing is landed on the casing hanger and anti-rotation pins are pressed upward as they contact a seal assembly. Thus the flexible material is connected to the container such that the cohesive portion can be readily secured to another cohesive portion to hold an article in a desired position in the container.