Wireless Bluetooth 4.1 ensures transmitting strong signal in high quality and high speed,delivering high-fidelity stereo music. With magnetic suction function, and when do not use headphone, you can easily wear the headphone on the neck, do not fall. Built-in microphone enables hands-free calls to set free your hands when doing sports. It also supports multi-point technology. Easily control playing / pausing, adjusting the volume, previous / next songs, answering / rejecting / ending calls. Ergonomic design guarantees wearing stable and comfortable when exercising, running, climbing and other outdoor sports. Specifications: Bluetooth Version: 4.1 Support: HFP, A2DP, AVRCP Working Distance Range: 10m Frequenc Responce: 20-20KHz Impedance: 32Ω Sensitivity: 105dB High-quality 3.7V / 60mAh Rechargeable Lithium Battery Charge Time: about 1.5 hours Standby Time: about 100 hours Talking Time: 2-4 hours Music Time: 2-4 hours (The music volume will affect the time) Charge Port: Micro USB Cable Length: Approx. 67cm / 2.19ft Headphone Weight: 14g / 0.50oz Package Size: Approx. 13.5 * 9.5 * 2.0cm / 5.31 * 3.74 * 0.73in Package Weight: 26g / 0.91oz Package List: 1 * Bluetooth Headset 1 * USB Cable 1 * User Manual