Cisco 7942G 7900 Series Unified IP Phone CP-7942G= POE, Communications Manager Required 5-inch (320 x 222),graphical monochrome 4-bit grayscale display Full-duplex speakerphone with acoustic echo cancellation. Four interactive soft keys that guide you through all call features and functions. More than 24 defined user-selectable ring tones are available. Intended to used via POE (Power Over Ethernet) (Communications Manager Required)