As a connecting element of shelves, end caps, shelf feet and shelf legs, the brace is the central element of the shelving system. The base of the brace is a folded sheet metal part, into which metal sleeves are welded, which are put on the dowel pins in the shelf legs. The two sliders in the strut are pushed into the vertical joint with a finger, thus connecting the lower and upper shelf legs. A signal color draws attention to the open state of the slider. When closing, this indication disappears under the sheet metal part.