Specifications: 1) Built-in MP3 format decoding chips 2) 14 channels for choosing 3) FM transmitter can automatically read the MP3 files from USB flash disk or MP3 player 4) Operating distance: up to 30 meters 5) Digital indicating (frequency and volume) 6) Channel isolation ratio: >=72dB 7) Frequency range: 20Hz - 15KHz 8) Working current: 50mA±10mA 9) Output current: 100mA max. 10) Accessories: audio cable (3.5mm - 2.5mm stereo) 11) Size: 9.5cm, 5cm remain long after plugging into cigarette lighter 12) Channel range: 87.7/87.9/88.1/88.3/88.5/88.7/88.9MHz, 106.7/106.9/107.1/107.3/107.5/107.7/107.9MHz How to use: 1) Plug the FM transmitter into cigarette lighter of your car 2) Plug the USB flash disk or MP3 player into the USB port 3) Press the CH button to select frequency 4) Turn on your FM Turner of your car, choose the frequency which the same frequency of the FM transmitter 5) Adjust volume to proper level, press Play button once, and then enjoy it 6) You can turn off the FM turner and plug the headset into audio port, enjoy music yourself 7) Except USB port, you can connect others music players by audio cable (included), such as MD, mobile, PDA, walkman Packing: N.W.: 34g G.W.: 92g (with blister and audio cable)