Yamaha PSS 11 Keyboard 100 sounds, 15 jam tracks, 32 midsize keys, 25 rhythms, 15 demos. The keys work very well and so does the sound quality. This was my dad's but he asked me to sell it for him. Some of the keys have letters drawn in pen on them. I cleaned them as much as I can. Works using a power ac adapter or six AA batteries but does not come with either. The battery opening in the back does not have a cover. Was a bit dusty but I cleaned it up.