About this article Smart QC 3.0 Fast ChargingBluetooth audio transmission adapterm has dual USB ports and can charge two devices at the same time. One is QC 3.0 USB port for fast charging, 4x faster than a standard charger. (Compatible with: QC2.0, Huawei FCP, Samsung and HTC.) With maximum power, the charging efficiency is more than 80%, so your device can be fully charged in a short time Bluetooth hands-free phoneExtended Bluetooth 5.0 technology enables a more stable connection and faster transmission. The built-in high-performance microphone with CVC noise reduction technology gives you a crystal-clear hands-free function after connecting Bluetooth. With just one press of a button, you can easily answer/end/reject calls and also dial the last number. Drive safer Multi-music playback modeEnjoy lossless stereo music transmission. The FM transmitter can play your favorite music from Bluetooth devices via FM signals to the car radio. The USB stick can be used to transfer and play MP3/WMA songs. This Bluetooth FM transmitter offers you wonderful car music and makes your journey more enjoyable Easy operation Connect this Bluetooth FM transmitter to the cigarette lighter socket. -Turn on the car's FM radio and select an empty frequency. -Then set the same frequency on the FM transmitter (87.5108.0 MHz). -Connect the phone to the transmitter(name as C57) via Bluetooth. With the wider frequency from 87.5 MHz to 108.0 MHz, you can get a more stable and consistent music experience without interference. Multiple Protections and Wide CompatibilityComes with built-in Smart IC, over-current protection, over-voltage protection, intelligent temperature control and short-circuit protection. This bluetooth FM transmitter can be paired with all Bluetooth devices for iPhone, iPad, iPod, tablet, Samsung, HTC, Sony and other Android smartphones.