Elecom Bluetooth Stereo Headset. Interface type: USB, Wireless range: 10 m, Bluetooth version: 2.1+EDR. Ear coupling: intraaural, Acoustic system: closed. Battery technology: Lithium Polymer (LiPo), Talk time: 4.5 h, Standby time: 90 h. Weight: 13 g. Compatibility: Telephone, Input voltage: 5 V, Input current: 0.15 A