The Electro-Harmonix Little Big Muff is a guitar effects pedal with three controls: Volume, Tone, and Sustain. This item is a junk item. It is recommended for those who are good at repairs. It was usable with battery power, and I used it about three times in live performances before it was dropped from my main setup. The exterior is in very good condition, I think. - Model Name: Little Big Muff - Brand Name: electro-harmonix - Control Knobs: Volume, Tone, Sustain - Power Input: 9V DC Thank you for viewing.