25-FEET (7.62m) 4 Gauge True Spec CCA(Copper Clad Aluminum) Power/Ground Wire - Matte black Soft Touch PVC Jacket Allows for Maximum Flexibility withstand Extreme Temperatures ( -104 to 221 Outer Diameter: 10.5mm,Core Diameter: 7.5mm - The Lower the Gauge Number, The Thicker the Wire. Thicker Wire Presents Less Resistance to Current COPPER CLAD ALUMINUM (CCA) - CCA Wiring Provides a Good Conductor for Power Transfer. This is the Most Economical Option When Choosing Power or Ground Wire. Systems that Require More Power Should Consider OFC Wiring. Perfect for Radio, Home Theatre, Automotive, Stereo, Robotics and R/C applications