• Plug the FM transmitter to car outlet lighter socket.
• Turn on the car radio, choose a station, and make sure the station is blank to avoid interference by local radio signal.
• Hold the fm transmitter answer key until the LED display flashing.
• Rotation the answer knob to adjust the same channel with car radio FM channel.
• Press the answer key to fix the channel. Please google blank or try different channels to achieve the best enjoy.
• The 3.1A USB charging port provides fast charging speed;can charge for ipad, big screen cellphone etc
• Another 1.0A designed to charge and read USB flash drive. Please use pure charge line when use this one charging.

Car Battery Voltage Function:

• For 12V car, voltage display of car battery under 11.5V or higher than 14.9V means car battery issue.

• For 24V car,voltage display of car battery under 23.1V or higher than 27.3V means car battery issue.

• Dual USB car charger: 2 USB charging port to charge most USB Devices. Input 12V/24V, 1a port with USB reading and charge function; smart 3. 1 A charge port which can intelligently identify Android or iPhone devices and charging.

• More compatibility: wireless Bluetooth FM transmitter adapter for car radio,transfer calling/MP3 music/Cellphone voices to car speaker.Compatible for iPad,iPhone,Samsung,Google,LG,HTC and Bluetooth Device.

• Hands free function: built-in microphone, switch to hands-free mode automatically from music playing status when receiving calls. Answer/reject/hand up/recall all in One key.

• Car battery voltage function: Show 3 seconds voltage when plug into the port. Always keep battery state of health. Then it turn to automatic play mode.

• Music playing:support Bluetooth /USB disk/TF card/ MP3/wma player. With anti-interference performance and CVC technology.Listening to music while charging. Automatically connect memorized paired when power on. 12-Month worry-free.