Commercial vehicle superstructure with load securing for double decker operation

The structure (1) has side walls (5, 6) including two vertically running double decker rails (8), which are opened into a loading chamber. A load securing bar (10) is vertically adjustably accommodated in the rails, and fixedly held in different heights. The rails form a T-groove with ribs, which constricts an opening to the loading chamber. The T-groove is opened into the loading chamber. The load securing bar includes a bead-like scoring protector strip adjacent to the side walls. The protector strip is made of plastic.