Jabra/GN Netcom Extreme. Interface type: micro USB, Wireless range: 10 m, Bluetooth version: 2.1+EDR. Impedance: 32 Ом, Acoustic system: open. Microphone sensitivity: 14 dB. Talk time: 5.5 h, Standby time: 252 h. Dimensions (WxDxH): 18.5 x 47 x 27.5 mm, Weight: 10 g