Plantronics-CS540 Convertible Wireless Headset HIGH QUALITY HEADSET: Wideband audio quality includes superior technology that eliminates Wi-Fi interference and acoustic protection against audio spikes. SUPERIOR RANGE: Wireless multitasking is easy with DECT 6.0 technology, allowing you to clearly communicate up to 350 feet away from your desk. LIGHTWEIGHT DESIGN: Sleek design for the most comfortable and lightest DECT headset on the market and includes one touch controls to answer or end calls. Narrowband or wideband: up to 6,800 Hz LONG LASTING BATTERY: Features an energy efficient adaptive power system to conserve battery life. Connects to Desk phone. Talk time- Up to 7 hr ADVANCED MICROPHONE TECHNOLOGY: Wireless headset includes an extended boom to improve microphone quality and features noise-canceling microphone that reduces background noise. NOTE- This headset is NOT Bluetooth compatible. KINDLY NOTE: Use with Electronic Hookswitch Cable or Handset Lifter (both sold separately) to remotely answer/end calls