Maxon RTD800 Real Tube Ovedrive/Distortion Guitar Effects Pedal Selectable Overdrive and Distortion circuits provide wide range of tube sounds, from traditional overdrive to high-gain distortion Post-distortion tube configuration for more realistic tube tone Three independent tone circuits to diminish cross-talk and frequency overlap, allowing for an unprecedented degree of tonal options Foot switchable boost circuitry with variable boost of 3-9 dB Power adaptor included