Plantronics .Audio 400 DSP (formerly DSP 400) offers collapsible design, ideal for easy storage and transport. USB digitally enhanced voice quality for Skype®, Windows Live™, or Yahoo® Messenger Internet calling; Easy set up - simply plug into your computer's USB port (no software needed); Listen to CDs, DVDs and MP3 files in stereo wherever your laptop goes. Full-range stereo sound; noise-canceling microphone for greater speech accuracy; inline digital volume and mute controls. Windows and Mac compatible. Part number 76921-11, formerly 76921-01. One year manufacturer's warranty.