The information below applies to one pack only. The function of this extension cable: 1. Extends the 4-pin CPU power supply cable. 2. Converts the 4-pin plug on an old power supply to an 8-pin plug to fit the 8-pin CPU power port on the motherboard. Plug and play, convenient and fast, with a safety lock at the plug to prevent accidental falling off or disconnection. 8 Inches (20cm), 1007 18AWG tin-plated copper wire with strong conductivity and resistance to corrosion and oxidation. The wire sheath is made of PVC and is insulated and flame retardant for added safety. The mesh sleeve effectively manages the wires inside your computer case, making your computer case look neater