Specifications: 1) Voltage: 12V DC 2) Operating current: 3) FM frequency: 14 channels, 7 lower frequencies (87.7 - 88.9MHz), 7 higher frequencies (106.7 - 107.9MHz) 4) Channel switch: press the CH key to switch preset channel 5) Audio source: USB flash disk or MP3 player 6) Transmitting distance: up to 30 meters 7) Can supply power for the other MP3 Instructions: 1) Plug the unit into cigarette lighter of your car directly 2) Plug USB flash dick into car MP3 transmitter through USB disk jack 3) Press the CH button to select one from 14 FM channels that do not interfere with local broadcasting stations 4) Tune the frequency of your car\'\'s stereo to the same as the unit 5) Press the play button on the FM modulator to enjoy your music