Copper clad steel wire or CCS wire combines a steel rod or steel wire as its core with a concentrically clad copper coating. The metallic cohesion provides this conductive wire with high tensile strength of steel and conductivity properties of copper. As the copper permanently bonded on the surface of the steel core, it efficiently prevents the steel from corrosion and allows a single of this bi-metal wire to be processed with drawing and annealing treatment. This CCS wire can maintain the ratio of copper and steel unchanged during the drawing process, while the copper volume ratio remains relatively constant. Since the signal itself travels on the outer edge of the center conductor which is called “skin effect”, this makes copper clad steel wire and copper clad aluminum wire possible to transmit high frequency signal (over 5MHz) with the same conductivity of the pure copper wire.