OPPO v4.1 Car Bluetooth Device with Audio Receiver, FM Transmitter, 3.5mm Connector, Remote Control, 3.5mm Connector  (Black)

INSTRUCTIONS FOR USE: Insert the receiver into the speaker's USB interface, and the other end connected with the 3.5mm audio cable to the receiver and the aux interface of speakers. Open the Bluetooth-enabled mobile phone (or computer), and search the surrounding Bluetooth devices to find a device called find its pairing code is 0000, after the pairing is successful, the LED light will slow down.