The invention relates to a kit (1) comprising finished slabs (2), particularly of concrete, by means of which trafficable surfaces such as parking spaces (3) or roadways that should simultaneously be planted with vegetation can be mounted. The finished slabs (2) constituting the substantial part of the kit (1) have a load-bearing region (4) to this end, oriented in the driving direction, for example, and bars departing and distant from a side in the transverse direction thereof, of equal length and connected to the load-bearing region (4) but offset from each other by an intermediate space (9), said bars (5) additionally having at least one additional support (7) or (10) at a distance from the load-bearing region (4) of the slab (2). The kit (1) comprises a plurality of such individual slabs (2), wherein the support (7) offset from the load-bearing region (4) is smaller than the load-bearing region (4) and is configured to be largely hidden. In order to configure a lane, at least two individual slabs (2) each can be placed such that the ends (6) of the bars (5) facing away from the load-bearing regions (4) are oriented toward each other and flush to each other, or facing away from each other, and/or make contact with each other (see Fig. 3).