This is a YAMAHA DX21. It's packed with sounds that still hold up today, from delicate tones to powerful ones. All keys produce sound. The keyboard is in good working order. The LCD screen has some blackening at the top and bottom, but it's still perfectly readable. The display is clear and functions normally. Pitch bend is normal. All buttons have been checked and confirmed to work. Outputs A and B are normal, and there is no scratchiness in the volume. No battery errors were detected at startup. The above checks were performed, but this is based on the current condition. Thank you for your understanding. Please understand that this is a vintage item, and there is no warranty. I have cleaned it, but there are some minor stains and scratches. Please check the photos. It's generally in good condition for its age, but please refrain from purchasing if you are overly sensitive. A rare music stand set is included! I will ship it quickly with air padding and corrugated cardboard. Thank you.