Car MP3, MP4 FM Transmitter, with USB key and SD-MMC card slot, 1.5 inch TFT screen FM Transmitter - Broadcast music from USB/SSD/players to your car stereo system over FM Frequency. Support SD/MMC card, and any other players attached by AUX cable Remember the last frequency and music, track and recall them when restarting Excellent sound quality with D.S.P solution for echo cancellation & noise suppression Handles MP3/WMA/WAV/WMV/ASF formats. Transmit frenquency 87.5-108MHz/Voltage 12-24V