Bluetooth 5.0 Transmitter Receiver 2 IN 1 Wireless Audio 3.5mm Jack Aux Adapter. Bluetooth5.0 2in1 Wireless Audio Transmitter Receiver HIFI Music/Adapter RCA AUX. 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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