Poly Savi 7220 Office Binaural Wireless Headset for desk phones lets you confidently roam up to 400' from the headset base. DECT adaptive power system optimizes range, saves power and maximizes office space. It automatically adjusts the wireless signal strength based on distance from the headset base. Charge lasts up to 12 hours of talk time. Charge indicator informs you when the headset is fully charged. Flexible, noise-canceling microphone boom easily adjusts for optimal placement on every call so conversations stay private. Collaboration is easy with conferencing up to four headsets on one base. Wireless headset offers instant integration with more than 800 analog and IP desk phones from industry-leading makers, including a wide range of phone options from Poly.