广泛的标准部分。一个ll rectangular and round sections are produced using a nominal copper cladding of 15% by volume (37% by weight) with the exception of certain sizes of high aspect ratio which are produced with nominally 20% copper by volume (45% by weight). Special profiles, for example ‘L‘ or ‘T‘ shapes can be made to order, and are produced with a 20% copper cladding by volume.