It also features a front AUX input for those who want to plug in their portable music players. This piece is compatible with MP3/WMA/AAC files. This receiver doesn't have any different features from that of the $80 priced Kenwood KDC-138, the extra cost of the DPX303 goes towards the large display screen. The target market would be people who care more about convenience than bells and whistles. Those who like a multitude of features and convenience can get the Kenwood DPX503 for an extra $70.