Behringer OD400 Ultimate Overdrive Effects The ultimate overdrive pedal for fat and big overdrive sounds with incredible dynamic response Dual-stage overdrive circuitry offers bigger and fuller sound with endless sustain and compression Blue status LED for effect on/off and battery check First-class electronic On/Off switch for highest signal integrity in bypass mode Runs on 9 V battery or the BEHRINGER PSU-SB DC power supply (not included)