The Casio CTK-800 61-Key Portable Keyboard has 61 touch-sensitive keys, 500 high-quality tones, 32-note polyphony, and 120 rhythms from all genres, and that's just the beginning. A mic input and 50 built-in songs make for an instant singalong! 8 digital effects, USB interface for computer connectivity, and MIDI transfer. 3-step lesson system with voice fingering guide makes teaching and learning a snap. The Casio CTK-800 is powered by 6 "AA" batteries (not included) or optional AD-5 AC power supply (see item # 338700).