Get the most out of your home audio system with high quality pure bare copper speaker wire from Monoprice! The speaker wire features two or four conductors made of high purity (greater than 99.95% pure) bare copper. Pure Bare Copper is a superior conductor to the copper clad aluminum (CCA) that is used in many other inexpensive speaker wire. CCA is only about 68% as conductive as pure bare copper and the additional resistance is added to the impedance of the speakers which can negatively effect the sound. For the wire to have no audible effect, the total wire resistance should be no more than 5% of the lowest impedance of your speakers. Even speakers rated for a nominal 8-ohms, may dip to as low as 4-ohms at some frequencies, which further reduces the total cable resistance allowed in the wire. Using Pure Bare Copper speaker wire ensures that the total load put on the amplifier remains as close as possible to the impedance curve of your speakers. Each conductor in the speaker wire is jacketed with color-coded PVC for easy polarity identification. The CL3 rating indicates that the cable complies with fire safety and insurance requirements, making it safe for use inside the walls of residential class buildings. It also means the wires can carry a surge of up to 300 watts, which is double of what the CL2 rating can carry (150 watts).