2-in-1 DESIGN: It is not only a transmitter, but also can be used as a bluetooth receiver! You just need pair the product with your bluetooth device, and use the provided 3.5mm cable to connect the product to your car AUX-in port, then you can enjoy it.BLUETOOTH 4.0: Get high quality audio sound than the bluetooth 3.0 version, both in playing music and answering calls.USB CHARGING: The transmitter comes with an USB 2.1A output, you can charge your cell phones, GPS and other digital devices with high charging speed.Siri Function: We add the Siri function to the Mpow Streambot Flex, thus you can activate the voice software by clicking the sided button.EASY TO USE: Pairing with most bluetooth & fm devices in the market, like car stereo and iPhone 6s/6 plus 5S SE, Samsung Galaxy S7/6 Edge S5 S4, Blackberry, Huawei and Android Mobile Phones.