Plantronics CS510 - Over-the-Head monaural Wireless Headset System &ndash; DECT 6.0 Hands-free up to 350 feet 1-touch call answer/end, volume increase or decrease, mute & flash controls Energy efficient adaptive power system optimizes for range & talk time Conference in up to 3 addition CS500 or Savi headsets for enhanced collaboration New headsets can subscribe to base by simply docking the headset. Ideal for Office and desk-centric workers across the enterprise looking for a simple-to-set-up, simple-to-use wireless offering for managing desk phone calls