An assembly kit for building a rack includes a plurality of longitudinal members to be arranged vertically, a plurality of cross members to be arranged horizontally, a plurality of node elements that connect the longitudinal members and cross members to each other, and a plurality of rails that accommodate rack bottoms, drawers, and the like. The longitudinal members are provided with holes used to hook in the rails on first lateral surfaces of the longitudinal members facing each other, wherein the holes are T-shaped and include breakouts adjacent to the first lateral surfaces. The rails are longer than the open distance of a front longitudinal member from a rear longitudinal member by the depth of the breakouts and are provided with U-shaped folded edges. The width of the vertically extending section of the T-shaped hole corresponds to the length of the free leg of the U-shaped folded edge.