A load module for inserting into a tube of a three-dimensional supporting tube structure of a furniture system comprises an elongate housing. Arranged on an outer side of the housing are two contact elements having different polarities for electrically contacting the load module. The contact elements arranged such that, with the load module in inserted states, they contact two contact surfaces of different polarity, which are arranged in the interior of the tube, in a radial direction. Housing has a central region in a longitudinal direction with at least one projecting element and outer regions in the longitudinal direction, the load module can be inserted into a tube, which is provided with an elongate opening, of the tube structure such that the at least one projecting element interacts with an edge of the opening, and the outer regions bear against an inner lateral surface of the tube in regions adjoining the opening. A first of the contact elements is arranged in a first circumferential position in one of the outer regions.