Southwire 56918245 500-Feet Dual Shields Type RG 6/U 18 AWG Coaxial Cable, Black Solid bare or Copper Conductors PVC Insulation 95-Percent Copper Braid, 300-Volt 80-Degree C Heat capacity Resistant to flame Southwire Type RG 6/U Coaxial Cable is made of copper clad steel for the center conductor and the braid on the coax is aluminum .