presents the image of a planar transverse wave as shown in fig4 for triangular profiling and in fig5 for sine shaped profiling the width of the individual undulations corresponds to the diameter of the largest grain size and the roughness depth or depths of the undulations measured from undulation base to undulation apex corresponds to half the diameter of the largest grain size in case of a biaxial arrangement of the undulations the surface to be coated is profiled in such a way that the undulations extend in two directions forming a right angle with one another at periodic spacings with recesses depths or rises summits and that after the surface treatment it exhibits a more or less uniform pattern of pits or summits as shown diagrammatically in fig6 the spacing of pits or summits is to be dimensioned in such a way that the depth of the roughness of the profiled surface corresponds to half the diameter of the largest grain and the spacing of the undulation bases 34 valleys 34 or the crests 34 mountains 34 corresponds to the diameter of the largest grains of the aggregate the establishment of profiling of the overlay areas according to the invention can be performed by different methods and apparatus several such apparatus and methods are as follows 1 water jet treatment water jet technology especially at high pressures can produce a single as well as a two axis profiled surface by adjusting the water pressure periodically in accordance with the triangular or sine curve function during the course of the treatment there results a more or less material removal on the surface to be treated and produces the desired single.