1. Bluetooth specification: Bluetooth V4.1. Support protocol Headset hands-free A2DP, AVRCP. 2. Transmission range: 10m, transmission frequency: 2.4GHz. 3. Charging voltage: DC5V, charging time about 2 hours. 4. Capacity: 30mAh, size: 70*25*30mm. 5. Talk time: over 4 hours, music time: over 5 hours, standby time: over 55 hours. 6. Electric quantity display (for Apple iPhone and part of Android mobile phones). 7. The streamlined design highlights the fashion-business modern style, showing the elegance; the in-ear type design is comfortable to both ears and suitable for wearing for a long time, and the product is easy to control and use.