Function 1.Car battery voltage detection 2.Bluetooth hands-free, then the built-in microphone, easy and safe to answer the telephone; 3.The noise processing call CVC, wind noise reduction, full duplex talking technology; 4.Phone support A2DP function, play high-quality mobile phone music directly after connecting Bluetooth; 5.Boot automatically after power back to the company, it automatically enters pairing state; 6.Support TF card expansion play MP3 / WMA format music; 7.Comes with car charger, output 5V-2100m, can charge handheld devices.