The PSR-F51 is the lowest cost entry-level portable keyboard that Yamaha offers. With 61 keys and basic features it's an easy choice for a first keyboard.61 full-sized keys are great for learning and developing keyboard playing technique. 32-note polyphony allows for the performance of beginner to advanced level pieces, allowing for sustained notes to ring through without being cut off. Auto power off saves energy by shutting down after a period of inactivity. Battery powered! Uses six 'AA ' batteries with five hours of life! Accompaniment Styles add a 'backing band ' to your performances while you remain in complete control of chord changes a nd a rra ngeme nts. Duo mode spl its the keyboa rd into two halves, each with their own 'middle C ' for practicing with a partner. PSR-F51 Survival Kit #J45842 (Optional)This essential addon contains everything you need to make using your Yamaha PSR- F51 just that much more enjoyable. This accessory bundle contains a power adapter.