9V Power Supply Adapter for M-Audio Keystation 61 MK3, 88 MK3 USB MIDI Keyboard | eBay
AC Adapter For M-Audio MAudio AXIOM Pro 25 Key 49 Key 61 Key 61-ES 61ES Oxygen 61 49 88 25 8 8 V2 USB MIDI Controller Keyboard - AliExpress
PwrON 9V AC to DC Adapter For M-Audio Keystation Line MAudio Midiman 9V, Keystation Pro 88, Key station 88es/49/49e/61/61es, Merge 3x8, MK-225/425C/449C/461C, OT-14, Oxygen 8, Portman 2x4/4x4s - Walmart.com