Maximm professional quality 12 AWG, 4 conductor speaker wire allows you to connect speakers to amplifiers and AV receivers easily and securely our American Wire Grade 12 speaker wire are constructed of high strand oxygen free copper alloy wires and are 99.9 percent free of surface oxygen. This lack of oxygen protects our wires from the harmful effects of corrosion while allowing for maximum conductivity and less power from your amplifier or electrical output. -The speaker wires CL3 Rating indicates safe use of our wires in-walls including drywall, brick, and wood surfaces. Encased in flexible plastic making installation around tight angles and corners easy. Casing is clearly marked in 2 foot intervals for easy and accurate measuring.