Allow for hands-free phone calls via Bluetooth using the integrated microphone. bolster the A2DP feature. As long as the mobile device is connected, music will be played directly. Built-in dual USB 5V/3.4A output and 5V/2.4A port support smart charging. The latter can detect and output the best and fastest charging current for mobile phones and tablets of all brands. Stylish and robust design featuring an LED frequency display. Voice number prompt in English. MP3/WMA music files can be played, and SD/TF memory cards and USB flash drives (up to 32GB maximum) can be read. This car MP3 wireless FM transmitter allows you to switch up your music from your usual playlist because it supports FM channels. The MP3 player is simple to use and transport; just plug it straight into your car's cigarette lighter.