Linkte Sk-s10 Bluetooth Wireless Mini Speaker Tf , Microphone, Mp3 Player Blue Color Bluetooth protocol: version 2.1+EDR 2. Bluetooth range: 10meters. Input sensitivity: 300MV 4. Frequency range:80Hz~20KHz Signal-to-noise ratio:&gt;76dB 6. Talking time: up to 5 hours Charging time: about 2 hours. 8. Power supply: USB Power