Commercial series antennas are constructed from Grade 6000 series aluminium and corrosion resistance is increased by a silver anodised finish. Elements are 12mm x 1.4mm extruded sections, which provides a robust antenna. The boom section is 25mm x 25mm x 1.7mm square tube, to which the elements are clamped. This system allows the aerial to be shipped knocked down. Cast aluminium clamps with stainless steel hardware are used to mount each element to the boom.