Abstract: Aluminum framing components comprise both hollow aluminum extrusions and open back aluminum extrusions which may be used separately or as a system. The hollow aluminum extrusions have a total of three screw bosses, two of which oppose each other on the side walls above the center of gravity of the extrusions and the third of which is located in close proximity to the bottom center of the extrusions below the center of gravity of the extrusions. A U-shaped clip may be fitted between these screw bosses to prevent the hollow aluminum extrusions from twisting or rocking during installation of the hollow aluminum extrusions to an upright such as an other hollow framing component and also permit field attachment of the hollow aluminum extrusions to such other hollow framing component upright for use as a chair rail or the like.

Abstract: Aluminum framing components comprise both a hollow aluminum extrusion and an open back aluminum extrusion which may be used separately or as a system. The hollow aluminum extrusion has a total of three screw bosses, two of which oppose each other on the side walls above the center of gravity of the extrusion. The third screw boss is located in close proximity to the bottom center of the extrusion below the center of gravity of the extrusion. The walls of the three screw bosses are thicker than the nominal wall thickness of the extrusion, and the extrusion walls directly behind the screw bosses are thicker than the walls of the screw bosses.