Harnessing the Power of Digital Voice Bring digitally enhanced audio quality and the comfort of Plantronics headsets to Voice over Internet Protocol (VoIP) softphones with the Plantronics DA55. The DA55 USB-to-headset adapter includes digital signal processing (DSP) for crisp, clear sound. Digital Clarity, Plantronics Comfort Plug the Plantronics DA55 directly into the computer s USB port and connect to your favorite Plantronics professional headset. Enhanced VoIP Sound Quality The DA55 combines echo suppression with Plantronics Call Clarity feature to deliver excellent audio quality for VoIP softphone applications. Technical Information - Number of Connectors: 2 - Connector Details: 1 x 4-pin Type A Male USB - Connector Details: 1 x Quick Disconnect