The invention relates to a one-piece connecting element (8) that connects a first wall panel (5.1) to a second wall panel (5.2). A first spring element (8.3) is mounted on the upper part (8.2) of the connecting element (8) and on the one side of a first bent piece (5.11). A foot (8.1) of the connecting element (8) is used as a counter bearing and is mounted on the other side of the bent piece (5.11). A second spring element (8.4) is mounted on the upper part (8.2) and on the one side of a second bent piece (5.21). The other side of the second bent piece (5.21) presses onto the one side of the first bent piece (5.11). The connecting element (8) is introduced into a first slot (11) of the first bent piece (5.11) without tools, and the second bent piece (5.21) is placed over the connecting element (8) on a second slot (12).
