The Aerpro APFM210 Full Frequency FM Transmitter allows you to enjoy music on the road even if your vehicle doesn't have an AUX or USB port. Plug the FM Transmitter into the accessory power socket in your vehicle and connect the 3.5mm AUX cable to your smartphone or music player and it will transmit your music to your vehicles FM radio. It also features Micro SD Card and USB inputs, enabling music playback from a memory card our USB drive. The USB port can also be used to charge your smartphone or other USB device. With the full FM frequency range to choose from, simply match the FM frequency on your radio with the frequency selected on the FM Transmitter.