Abstract: A device for adjustably mounting facing plates on a structure includes an elongated L-shaped supporting member made up of a first leg or web and a second leg or web. One surface on each of the first and second legs of the supporting member is toothed. An abutment also having a toothed surface is arranged to intermesh with the toothed surface on the first leg of the supporting member. The toothed surface of the second leg extends in the long direction of the supporting member and intermeshes with a similar toothed surface on a supporting plate. Supporting bolts are connected to the supporting plate and project into receiving holes in the facing plates. The second leg of the supporting member has an opening through which one of the supporting bolts can pass. For aligning adjacent facing plates the transversely extending dimensions of the opening in the second plate are selected as multiples of the diameter of the supporting bolts.