Sound Storm Laboratories SDC24USA MP3/CD Detachable Front Panel, AM/FM Music Player Remote Control View larger General Features AUX (Auxiliary) In - This little input in the front of the SDC24USA that says “AUX” is an interface that allows the input of audio signals for MP3 players, headphones and portable music players. It is for audio only and not video. Switchable US & Europe Tuner Frequencies - If you happen to take the SDC24USA outside of the US, you are able to pick up European frequencies so that you can enjoy your music abroad as well. Output Power: 50 Watts x 4 Channels - The SDC24USA offers 4 channels that can be used to hook up 4 speakers. Typically though, it is a much better practice to have an amplifier running your system. Front and Rear OutputsPre-Amp Outputs AM/FM Receiver Playback: CD±RW Audio / MP3 / WMA Compatible With Audio Output of iPod / iPhone, Smartphones and MP3 Players View larger Rear View Of the SDC24USA View larger Compatible With Audio Output of iPod / iPhone, Smartphones and MP3 Players A great feature that comes in really handy is that little hole in the front of your unit that says “AUX”. What this means is that if you can connect a device that has an Auxiliary output, such as your iPhone/iPod, smartphone and MP3 players straight into the Auxiliary input of your head unit. So basically a cable that has (2) 3.5mm audio (male) plugs. Important: Please beware that this feature is not the same as the “Full iPod Control”. This feature will only allow you to control your music by clicking on the designated buttons via the face or front side of your unit. USB and SD Ports View larger USB and SD Ports The USB and SD ports are located directly in the front of the SDC24USA so that they are able to easily and quickly access all of your favorite Audio and Video entertainment needs.