2 USB charging 5 V / 2.4 A charging process and 5 V / 1A (with music symbol) charging port enable faster and more stable charging speed. Dual Port Charge Intelligent Distribution 3.4A Single port charge up to 3.4A. 3 Music Game Model Had the FM transmitter bluetooth, you can enjoy crystal clear music through 3 modes: bluetooth, TF card (32GB) and USB stick (32GB). Supports music form: MP3, WAV, WMA, FLAC, APE. Safe Driving: With this wireless device, you can easily answer / reject / redial calls by hands-free calling and drive safely. Noise and wind are suppressed by the CVC technology and ensure full duplex sound quality. Car battery voltage display The car transmitter displays the vehicle voltage as soon as it is connected to the car'slighter. Then you can know the car battery condition easily. Quick and easy pairing: Plug this wireless car kit into thelighter socket, tune the FM car radio to an empty station (87.5-108.0 MHz) and set the FM transmitter to the same station. Pair with your cell phone via bluetooth and enjoy your music. Hands-free:Click the MFB button to answer / redial / hang up or reject calls. It easily switches between incoming calls and music. 3 game music sources:Press the "Mode" button to switch music sources from Bluetooth / TF Card / USB disk. To play music on the USB port, insert the USB flash drive with your audio files and the NX09 will recognize and play the music automatically. 2 USB charging ports:With 2 USB(5V-2.4A and 5V-1A) you can charge two of your devices simultaneously via this FM transmitter while driving.