1. Frequency and track memory function 2. built-in flash memory 3. LED display 4. SD Card Slot & USB Port. 5. Reads MP3 files from USB flash disk or SD/MMC card, transmits music signal over car FM tuner, then enjoys music via car stereo 6. Supports external audio player: MP3 player, CD, and VCD 7. Draws power from the cigarette lighter in the car (DC12V power) 8. FM channels: 87-107.9MHz 9. Excellent sound quality, extreme music experience Instructions: 1) Plug the unit into cigarette lighter of your car directly 2) Plug USB flash dick into car MP3 transmitter through U 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