Specifications:Material: ABSBluetooth version: 5.0Bluetooth band: 2.4 GHz-2.48 GHzBluetooth Transmiion distance: 5mFM frequency: 87.5-108 mhzFM transfer distance: 2 metersInput voltage: 12-24VOutput: 5V/3.1ADescription:-High Performance Bluetooth FM Transmitter: Solid Bluetooth and FM connections stream music straight from your phone to your cars sound system.-Easy Pair: Easily pair your smartphone in seconds and stream music straight from your phone to your car's sound system. This will automatically connect to its memorized paired Bluetooth device when power on.-Voltage Display: Voltage display feature ensures security reminder at a glance.-Hands-Free Calls: Bluetooth 5.0 technology provides a stable connection and echo-cancellation reduces background noise for clearer calls. Built-in microphone with Echo Cancellation and Noise Suppreion (CVC) technology can effectively create full duplex sound quality. Easily answering/redialing/dismiing or ending a call just simply click a button.-Dual USB Ports: Comes with 5V-2.1A and 5V-1A two charging ports, you can get your devices full charged in short time, support charging two devices simultaneously. Help you enjoy in-car stereo streaming and charge Your smart device at the same time.-Music Playing: Support Bluetooth Music/ USB Disk MP3 music player. Connect your Smart phones or other Bluetooth enabled devices via Bluetooth to streaming your music, or you can insert a USB flash drive (max capacity 32GB) to enjoy your music. Stream music and calls directly from your Mobile devices to car stereo -system via FM radio signal (87.5-108.0 MHz).Safety: Ensure driving safe without disturbance.-Compatibility: Fit for most of the smartphones, tablet and more devices that equipped with Bluetooth function, such as, iPhone, iPad, iPod, Tablet, Samsung, and other Android Smartphones.Notice:1.the item comes without the retail packing box because it will increase the