Bluetooth 5.0 Transmitter Receiver Transmitter 2in1 Aux Audio Adapter Headphones. Wireless Bluetooth 5.1 Receiver Dongle Car AUX 3.5mm Adapter Cable. Turn on the speaker, plug the product into the docking seat, and the front and rear LED lights begin to flash rapidly, indicating that it has entered the pairing mode, indicating that the device is working normally.
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