Straight Wire Musicable II Subwoofer Single RCA to Dual RCA's 4.0 Meter Interconnect Oxygen Free Copper Conductors for accurate signal transfer. Foam Polypropylene Insulation preserves an open soundstage. Dual Braid & Foil Sheilds to reject distortion & external noise. Star-Quad Design used in pro studios for long runs. Matte Navy Blue Jacket, 6mm (.23") diameter.