Abstract: The present invention provides an assembly of a first panel formed with at least one insertion notch extending inwardly from at least one panel edge and a second panel carrying at least one projecting tab extending outwardly of at least one of its edge and fitting in one of the notches. The tab has on at least one of its sides a shoulder defining an edge which is located along the projecting length of the tab at a position intermediate the free edge of the tab and its base, which usually coincides with the edge of the panel from which it projects. The shoulder edge is in abutting contact with a region of the first panel adjacent the insertion notch in the first panel in which the tab fits and functions to maintain the associated edge of the second panel out of contact with the first panel so that the relative positions of the panels is determined by such abutting contact and is independent of other factors, such as the precise linearity of the panel edge.

Abstract: The present invention provides an assembly of a first panel formed with at least one insertion slot and a second panel carrying at least one projecting tab extending outwardly of at least one of its edges and fitting in the slot. The tab has on at least one of its sides a shoulder defining an edge which is located along the projecting length of the tab at a position intermediate the free edge of the tab and its base. The shoulder edge is in abutting contact with a region of the first panel adjacent one of the insertion slot and thus maintains the associated edge of the second panel out of contact with the first panel so that the relative positions of the panels is determined by such abutting contact. The first and second panels can be positively secured together by means of an interconnection element, preferably in the form of an integral flange bent up from one of the panels, which is attached to one or both other panel by screws, bolts and nuts or similar attachment devices.