1. Transform your wired speaker into wireless speaker, or acoustic speaker into car bluetooth speaker.
2. Built in microphone, support MP3 playing, handsfree call, AUX output and card reader function.
3. Support 32GB Micro SD / TF card, the card is not included in this item.
4. The USB port can be two-sided connected.
5. Bluetooth 3.0 version, most of mobile phones, tablets can be connected to this item.
6. Please note that some of the car USB port has the function of data transmission, when you connect the receiver to these USE ports, it will turn to card reader mode first, you need to long press the call pick up key to switch to the bluetooth mode.