This is for a used Yamaha AG Stomp pedal, the acoustic multi-instrumentalist's best friend for studio and live performances. It comes with the power supply and a copy of the manual. It has Yamaha's great mic modeling, compression, reverb, semi parametric eq, delay, chorus, and feedback suppression. All can be used at once. If you use more than 1 instrument on stage you can set up banks or presets for each to level the volume between them and not drive your sound man, the guys in the band, or the crowd crazy. The feedback suppression allows acoustic playing at high volumes. This is a pro pedal with L, R, phones, and MIDI out.