Aluminum. To protect nose of stair. 1-1/8'. Screw nails included. Carpet metal installation on concrete surface suggestion: Drill a hole in the concrete, insert a 3/16' x 1-1/4' or 1/4' x 1-1/4' wood dowel. Use the screw nails provided with carpet metals, insert into dowel, expanding the dowel to lock in place.