The invention relates to a coiled composite sheet material far brazing, the composite sheet material having a structure comprising a substrate, the substrate including an aluminium substrate and/or an aluminium alloy substrate, on at least one side coupled to a carrier layer having a thickness of at most 150 m and additionally a polymer being homopolymers of olefin, or a copolymer of an olefin and a non-olefinic comonomer copolymerizable with the olefin being vinyl monomer, acrylic acid, methacrylic acid and/or acetic acid as a carder filled with a brazing flux material.