Dual USB Ports & QUICK 3.0- Two USB ports for charging devices, it has two USB charging ports, can charge two devices at the same time, and has over-charging protection. One port is the Quick Charge 3.0 port, which can fully charge your device in a short time. With a built-in microphone, this Bluetooth FM transmitter allows you to easily answer, hang up, reject calls or redial the last number. Fast Pairing and Easy Operation- This upgraded Bluetooth fm transmitter is designed with highly optimized Bluetooth solution, using Bluetooth V4.0, the Bluetooth connection is fast and can connect automatically. The connection is more stable. Excellent HI-FI Crystal Clear Stereo Sound- CVC technology suppresses noise and wind, creating full-duplex sound quality; Supports MP3/wma/wav, anti-static design, enjoy lossless music in the car! Wide Compatibility-Uses U Disk (64G). Compatible with most Bluetooth-equipped smartphones and more.