A tool for opening an extruded profiled body of a power cord assembly device includes at least one pair of guides and at least one support, the pair of guides and the support being arranged in a frame, wherein a first guide of the pair of guides is arranged and shaped to releasably connect to the an interconnection area of the profiled body, and wherein a second guide of the pair of guides is arranged and shaped to releasably connect to a second interconnection area of the profiled body, said support being provided with a support member adapted to bear against a portion of the first wall opposite to a slit in the profiled body, the distance of the pair of guides relative to the support being such that the slit is widened in the area of the elongation of the profiled body where the tool is applied, thereby allowing a fiber optic cable to be introduced into the chamber.