eature: 1. Small appearance size, practical in most of the cars 2. Support bluetooth 4.0/3.0/2.0, Support voice & calling prompt & hands-free 3. Support charger for Android & Iphone or other device, max. Output 5V/3.1A 4. Full frequency FM transmitter, total support 208 frequency 5. Digital Display convenient for you are at the darkness 6. Support TF card/U disk Not included MP3 music play 7. Bluetooth answer, hang up, reject, redial calls & other functions 8. Echo cancellation & noise suppression (CVC) technology during a call 9. Automatic power-off memory function 10. Bluetooth stereo A2DP music play Specification: Material ABS & Metal Color Black LCD Digital Color Red Output Interface USB (Universal Serial Bus) 5V/3.1A Input Voltage DC 12-24V Output Voltage DC 5V 2.4A FM Frequency 87.5-108. Mhz Bluetooth Version 4.0+EDR Bluetooth Distance 10~15m Play format MP3 SNR ≥68d B Work Temperature 10~70 Using Bluetooth function: 1. Using Bluetooth for the first time, you need to pair your mobile phone with this unit. Activate your mobile phone's bluetooth function, then search new device. When the mobile phone detects this unit (named as BT Carkit-30") please pair & connect by using the original password "0000" 2. In the music playing mode, when there is an incoming call, this unit will automatically switch to telephone mode. Note: The Bluetooth indicator light which on the top of the screen will be stop flashing after the Bluetooth connected with "