Rutba v4.1 Car Bluetooth Device with 3.5mm Connector, Audio Receiver, Car Charger, FM Player, MP3 Player  (Black)

Car Charger FM Transmitter&Music adapter,2.1A Dual USB Port 1.0A Dual USB : One is 1A, can charge small screen cellphone,camera and read USB dataThe device FM frequency is 87.5-108MHz.Please turn car radio channels to one of Frequency 87.5-108.0Mhz.Then plug the device, make sure the car kit keeps the same frequency to the car radio channels: 1.Choose an blank and clear channel in the car audio. 2.Long press the FM transmitter answer key until the LED display flashing. 3.Turning the answer knob adjust the same channel at FM transmitter. 4.Short press the answer key to fix the channel. 5.Connect phone bluetooth or insert the USB/TF card, FM Transmitter will start to play. Please repeat above steps if has noise interference in the radio. 3.Bluetooth Function : 1.Power on the device, there is a prompt voice : Bluetooth is ready to pair.