1.black and red speaker cable 2.4, 6, 8, 10, 12, 14, 16, 18, 20, ... side is the transparent protective cover of PVC (Red of Black). This type of cable is applicable to acoustic equipment.specification:Item NO ... /roll or 305m/roll100m/plastic spool or 305m/plastic spoolRed/black speaker cable, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22 ...