The Cisco IP Phone Power Cube (CP-PWR-CUBE) is used to supply power to the Cisco 7900 series IP phones when in-line Power Over Ethernet (PoE) is not available. The CP-PWR-CUBE AC power adapter is commonly used to provide the Cisco CP-7940G power, the Cisco 7960G power, the Cisco CP-7912 power, and the Cisco CP-7912 power. CP-PWR-CUBE-3