6 Construction elements made of metal used in concrete and other anchoring systems, namely, wedges, anchors, chucks, donuts, and couplers; Construction materials in the nature of metal post-tensioning concrete components and equipment, namely, anchors, anchorage systems, strands, tendons, wedges, staplers, staples for construction or industrial use, extrusion lines, cutting lines, and fabrication lines; Metal barrier cable systems and components, namely, anchors, inserts, wedges, rails, and swivels