AC/DC Wire And Supply Black And Red 8 Gauge GXL Automotive High Temp Pure Copper Stranded Wire - 25 Feet Ea Made In USA O.D SIZE IS .215 Pure Copper APPLICATIONS GXL is USED for a low voltage primary wire intended for use at nominal system voltages. GXL is ideal for high temperature applications with limited exposure to fluids and physical abuse experienced during the operation of cars, boats, trucks, buses, tractors, trailers, etc.