Aurum Cables - 18/4 Awg - 250 ft In Wall - Oxygen Free Pure Copper Speaker Cable - CL2 Rated UL Listed - 250 Feet 18 Gauge 24 Conductor - 250 Ft Rated for CL2 for in-wall installations and UL rated and certified Perfect for any DIY projects or custom installations 99.99% Oxygen Free Copper Comes in a Handy spool for easy installation and deployment.