The CS540, with HL-10 Lifter, features the lightest DECT™ headset on the market, a new streamlined design and improved performance. Go mobile and multi-task up to 350 feet (100 meters) from your desk with answer, end and mute controls at your fingertips. wireless headset system combines clarity of corded technology with mobility of wireless.  Headset choices for your personal style. Enjoy the sleek contemporary design of the new system, premium wideband audio quality.  Gain mobility - multitask, hands-free up to 350 feet (100 meters)  One-touch call answer/end, vol +/-, mute and flash controls  Energy efficient adaptive power system optimizes for range and talk time  Conference in up to three additional CS500 or Savi headsets for enhanced collaboration  New headsets can subscribe to a base by simply docking the headset  Use with Electronic Hookswitch Cable or Handset Lifter to remotely answer/end calls  • DECT technology provides better audio; eliminates interference from Wi-Fi networks  • Advanced wideband audio using CAT-iq technology for high definition voice quality  • Noise-canceling microphone reduces background noise interruptions, ensuring great audio quality and easing listener fatigue  • Enhanced Digital Signal Processing (DSP) provides  more natural sounding voice  Connects to Desk phone  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  Talk time Up to 7 hours (CS540);  Headset weight Convertible: 21 grams;  Over-the-head (monaural): 72 grams;  Over-the-head (binaural): 94 grams  Wireless frequency DECT6.0, range up to 350 ft  Audio performance Narrowband or wideband: up to 6,800 Hz  Hearing protection SoundGuard ®: protects against sound levels above 118dBA  SoundGuard ® DIGITAL : protects against sound levels above 118dBA; Anti-startle detects and eliminates any large sudden increase in signal level; Time-Weighted Average prevents average noise level from exceeding 85dBA  Limited warranty 1 year