The XIA-EU1 will allow the user to listen to an iPOD, XM Satellite radio requiring the Terk XMDirect tuner (sold separately), or an auxiliary audio input through rcas or any combination of two of the three sources. Since the audio is directly fed into the factory radio the sound quality is much more superior then a traditional FM modulator. Also the factory radio will control the iPOD and the XM Satellite radio and if the factory radio is capable of text it will display information from that source.