Red and Black RVB 2 Cores Flat Speaker Wire and Cable, is a flat-shape parallel soft wire with no sheath, also known as red and black cable. Red and Black RVB 2 Cores Flat Speaker Wire and Cable, is made up of two parallel lines, a red and a black insulated copper wire bonding together. The red side of RVB cable stands for the positive pole and the black size of RVB cable stands for negative pole. Red and Black RVB 2 Cores Flat Speaker Wire and Cables are mainly used for indoor installation, such as electrical appliances, household illumination, broadcast sound connection, fire extinguishing system, etc.