US 9V Power Adaptor for the Casio CTK-800 Keyboard by myVolts
Amazon.com: MaxLLTo 6ft Extra Long 9V 850mA AC Power Replacement Adapter for Casio CTK-700 CTK-800 CTK-900 CTK-2000 CTK2100 Keyboard Wall Charger Power Supply Cord : Musical Instruments
Casio CTK-591 Keyboard - Evolution Music
Casio CTK800 61-Key Full Size Keyboard w/Mic-In/Stand/Adapter - QVC.com