Plantronics CS55 Wireless Headset- Base and Earpiece System.
This includes the base, power supply and headband.
SUPERIOR SOUND QUALITY AND HANDS-FREE CONVENIENCE
Noise-canceling microphone filters out background noise
Up to eight hours talk time per battery charge
Roam up to 300 feet from your office phone
Remote ring detection
Call control at your finger tips: call answer/end, volume +/-
Convertible: over-the-ear, over-the-head or optional neckband for behind-the-head
1.9GHz frequency for clear, private, secure conversations
HL10 Handset Lifter enables remote call answering
http://www.plantronics.com/us/media/media-resources/literature/user_guides/CS55_UG_EN.pdf