Great little midi controller used it for drum programming in GarageBand and piano etc. Not getting any use at the moment so it's time to go.

No power supply but it powered via USB just fine. Never needed it to be plugged in, just ran it via USB and GarageBand picked it up no dramas. Comes with USB cable. In great condition.

Please check my other listings.

Portable, flexible, self-contained MIDI control!

The M-Audio Oxygen 8 v2 25-Key USB MIDI Controller is a 25-note velocity-sensitive, synth-action keyboard with +/-4 octave transposition. You get hands-on control of any 8 MIDI-assignable parameters within your favorite software programs. The Oxygen 8 v2 speaks directly to your computer without any extra devices or even a MIDI interface. Upgrades from the original version include class compliancy, transport controls, Enigma software editor for setup management, snapshot function, and plus/minus data buttons. Like the original Oxygen 8 keyboard controller it features 8 MIDI assignable knobs, one assignable slider, and a 25-key keyboard controller. It inputs and outputs 16 channels of MIDI to the computer via its USB port. Powered by USB or optional power supply, the M-Audio Oxygen 8 is light, compact, and highly portable.

Total MIDI control

MIDI isn't just about triggering notes--and the Oxygen keyboard controller has what it takes to access all those deep parameters in your software and hardware so you can get the most out of them. Map the eight knobs to any synth parameters you want to program or perform with?or to mixer controls like volume, panning and effects send. Assign the buttons to trigger samples and anything else that is MIDI-programmable. Assignment is simple, yet has the power to let you delve as deep as you want. Each MIDI controller can map to just about any applicable parameter in the MIDI spec, including independent channel addressing for each. The possibilities are limited only by your imagination.