Plantronics Blackwire C220M headset for Microsoft Office CommunicatorUSB enhanced digital sound Noise-canceling microphone limits outside noise, ensuring great audio quality and easing listener fatigueDigital Signal Processing and wideband frequency optimizes audio for more natural voice qualityHi-Fi audio with stereo sound optimizes music and video qualityWideband microphone provides the best PC audio telephony availableSoundGuard protects against instantaneous sound spikes above 118 dB SPL (sound pressure level)Easy to use inline controls equipped with call answer/end, mute and volume +/-Optimized for Microsoft Office Communicator 2007Standard version supports leading softphone vendors; Avaya, Cisco, IBM and moreChoose total-focus sound reduction (binaural design) or converse easily with co-workers while wearing the headset (monaural design)Ideal for occasional users of PC audio, video, webinars, conference calls, live PC presentations with desktop sharing, music, A/V presentationsPL8029902