Our USB CD player for car connect to the USB port of the car stereo/radio, turn on the power and insert the CD, then will automatically read the disc. The external CD player for car just be connect the USB port of the CD player to the to the car's USB port and turn on the power, using the AUX audio extension cable to connect the car and the AUX port of the CD player, then select AUX mode on the car screen to play songs from the CD.
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