<p>The device has fastening devices for attaching an external structure (105) at a side wall (102) of an electricity meter and/or distribution cabinet (101) at different distances to a rear wall. The distances are adjusted continuously or in steps and correspond to different positions of a locking lug in a locking teeth system or a connecting screw in an elongated hole. The fastening devices have a separate connecting piece (106) attached to the cabinet in the positions. Pins projecting from the connecting piece engage in an opening in the side wall.</p>
