2 USB Ports - This fm transmitter has 2 USB ports: one is designed for charnd the other one is for reading USB files. This feature enables you to play music and charge your phone or other devices simultaneously;4 Playing Sources - This fm transmitter supports 4 playing sources: Bluetooth, TF card, USB flash drive and 3.5mm Audio cable. Short press“Mode”button to switch the playing sources;Enjoy Large Screen - Our bluetooth fm transmitter can display song names, the incoming call number and monitor voltage of car battery;Crystal Sound Effect - This fm transmitter utilizes the most advanced interference and noise cancellation technology, which provides crystal sound quality and more stable signal;WHAT IS MORE - Built-in microphone feature supports hands-free talking; support TF/Micro SD Card in FAT format up to 32G; support A2DP; support MP3/WMA format; support AUX output and input.Our Bluetooth fm transmitter utilizes Bluetooth 3.0 technology which provides multi-solutions for your hands-free driving and in-car stereo streaming. Smartphones could be connected to this fm transmitter through Bluetooth, and then streamed through car fm system or AUX port. Easy to Use - Effortless pairing with Bluetooth stereo headsets, headphones, speakers, and other Bluetooth audio systems. Automatically pairs upon powering on 4 Playing Sources - Supports Bluetooth, TF card, USB flash drive, and 3.5mm audio cable for versatile music playback LED Large Screen Display - Displays song names, incoming call numbers, and monitors car battery voltage for convenience 2 USB Ports - One port for charging devices and another for reading USB files, allowing simultaneous music playback and device charging Wide Compatibility - Compatible with various devices, ensuring seamless connectivity and functionality