Plantronics HW251N is GREAT for VoIP phones (Cisco, Avaya, etc). An Ultra Noise-Canceling microphone filters out excessive background sound to further heighten call clarity. Designed for over-the-head comfort, Plantronics HW251N SupraPlus Wideband lets users choose between experiencing total-focus sound reduction (Binaural - 2 ear design -Plantronics HW261N ) or conversing easily with coworkers without removing the headset (Monaural design - this headset).
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