Alvinizer voice button to sound like Alvin! Hold up to 2000 songs with lyrics! Play MP3 files with lyrics on 3.5 in. screen. Includes 250 songs, key changer (Steps +1/-1) and USB slot for charging iPod or pesonal players. Built-in personal player holder with two microphone inuts and a microphone. Auto voice control, key controls and echo. Operates on 120V.