[Quick pairing automatic reconnection] After booting up the Bluetooth 5.0AUX receiver, you will be able to quickly pair with the mobile phone. After the device is connected to Bluetooth successfully, the blue light slowly flashes (time interval 10-20S). Next time you use it, the Bluetooth adapter will connect to the phone automatically. Bluetooth Aux Adapter 5.0: aux Bluetooth receiver can help you add Bluetooth function to the car or home audio, and turn the non-Bluetooth devices into Bluetooth wireless playback. It also supports sharing music through connection with TV, speakers, and stereo together.It is not only conducive to car entertainment, but also be able to save the cost of modifying old cars without Bluetooth. Hands-free callingThe Bluetooth car auxiliary receiver also has a built-in microphone for hands-free calling. In addition, it also supports connecting 2 different smart-phones at the same time. You can switch between the two phones as you wish. It can not only ensure safety while driving, but also is the best companion for your journey Plug and play: It supports instant plug and play. When you start/stop the engine, the auxiliary Bluetooth adapter will automatically turn on/off. Just plug it into the 3.5mmauxjack and supply it with power through the USB port (e.g. car USB port/car cigarette lighter/mobile power supply/computer/charger), you will be able to make calls and navigate instructions through smart Siri/Google Assistant, and enjoy perfect voice control while driving.