4 in 1 Wireless Bluetooth FM Transmitter FM Modulator Radio Car Mp3 Player Handsfree Car Kit with 2-Port USB Charging, Music Control and Hands-Free Calling(Gold) Exquisite appearance and will automatically detect the charging device and charging environment, match the optimal current, display output current value,more intelligent than others Automatically play and transmit the MP3 files of USB driver ,Micro SD card directly, Supports dual USB output voltage, power supply for other devices, the maximum output 5V/2.5A. Automatic memory function of power failure frequency point Excellent hi-fi stereo sound quality.High-performance built-in microphone with Echo cancellation and noise suppression (CVC) technology which can offer your clear talking and wonderful music.Bluetooth sound processing:A2DP Bluetooth version:2.1+EDR . Simply paired your phone with the Bluetooth FM Transmitter and its hands-free system can set free your hands during answer the calls and let you safely drive Compatibility: Compatible with Apple , Samsung , HTC , LG , Sony , Motorola , Nokia , ASUS , Microsoft & More Smartphones , Tablets & MP3 Players and other mobile devices