Crystal clear playback & 3 music game model If the FM transmitter Bluetooth, you can enjoy crystal clear music through 3 modes: Bluetooth, SD card (32GB) and USB stick (32GB). Supports music form: MP3, WAV, WMA, FLAC, APE.2 USB ports car charger The Bluetooth FM transmitter provides you with 2 USB ports. 5V/2.4A for charging and 5V/1A (with music symbol) for detecting USB stick or charging. Charge 2 devices at the same time.Hands-free & Navigation Answer / Reject / Forward / Redial in one button, automatically switch between incoming calls and music. This Bluetooth adapter is compatible with the existing navigation app on your phone. No need to look down to ensure safe driving.Car battery voltage display and ambient lightThe transmitter car displays the vehicle voltage as soon as it is connected to the car cigarette lighter. Then you can easily know the car battery condition. The blue light circle below simplifies operation for safe driving.Wide compatibilityThis hands-free kit can be paired with any Bluetooth device. Suitable for iPhone, iPad, Samsung, HTC, Blackberry, Sony, Tablet and other Bluetooth enabled devices such as MP3, MP4 players. With the wider frequency from 87.5 MHz to 108 MHz, you get a more stable and consistent music experience without interference.Reliable hands-free system:Bluetooth 4.2 delivers strong and stable connections for reliable hands-free calls.This built-in microphone completely frees your hands and provides you a safe and relaxed driving experience.Intelligent voice navigation:Connected to your mobile phone via Bluetooth, the FM transmitter car announces you to navigate from the app of your mobile phone.Please enjoy effortless driving on your trip.Dual USB port and secure charging:Supports simultaneous charging of 2 devices and provides protection against overcharging.The USB port (5V/1A) can recognize USB stick, another (5V/2.4A) can charge your iOS or Android device efficiently.