Abstract: An elongated rail having a cross-section with hook-shaped shelf projections, and adapted for extrusion, is secured to a wall by fastenings and adhesive for transfer of stresses to the stud structure of the wall. The rail has a substantial back portion providing a surface for receiving the adhesive, and for establishing a substantial moment of inertia in bending. Short pieces of the same rail section are secured to the back of the cabinet units in inverted position with respect to the wall rail for hooked interengagement. An abutment is interposed between the bottom of the cabinet units and the wall to maintain the vertical alignment of the cabinet units in selected positions along the wall.