ER9 2 in 1 Hands-Free Calling Car Kit Wireless Bluetooth Headset Dual USB Charger FM Transmitter MP3 Music Player

1. The device can detect battery's voltage.
2. Support Bluetooth headset to answer call,high-definition call.
3. Dual USB output total 5V/3.1A for charge mobile phone.
4. Support USB flash device and TF card playing music.
5. FM transmitter range: 87.5 to 108MHz.