Key Features: Monaural voice tube design. Adjustable headband Plantronics QD (Quick Disconnect) allows walk away convenience and compatibility Visual and tactile positioning guides enable precise and quick microphone positioning (HW510/HW520) Wideband audio for rich, clear conversations SoundGuard technology protects from noise spikes and listening fatigue Laser welded construction and metal joints provide unbeatable toughness Extraordinary Service
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