Behringer SM400 Super High-Gain Distortion Effects Bust down concrete walls with brutal distortion, mind-blowing sustain and the sound of an overdriven stacked tube amp Super high-gain design for ultimate dynamic response and a tone range from mild and crunchy to heavy metal and thrash Dedicated Distortion, 2-band EQ and Level controls for awesome sound shaping Blue status LED for effect on/off and battery check Runs on 9 V battery or the BEHRINGER PSU-SB DC power supply (not included)