The Plantronics CS520-XD is a wireless headset that provides clear communication even when away from your desk. It features wideband audio and noise-canceling technology for excellent sound quality. The headset has a comfortable over-the-head wearing style and convenient one-touch call management buttons. With up to 9 hours of battery life, it ensures productivity throughout the day. To use it with a corded desk phone, you will need to purchase an Electronic Hookswitch Cable or Handset Lifter separately. The CS520-XD is a great option for those seeking a wireless headset that offers clear calls, comfort, ease of use, and long battery life.