Nady TA-40 Tube Amp Simulator Superdrive Floor Effect Pedal 100% Analog circuitry offers rich, warm overdrive sounds which emulate the power amp output stage distortion of different classic guitar amps in a handy foot pedal Class A/B Drive knob controls the amount of odd harmonic class A/B power amp output stage distortion and together with the specially designed, musical Tone control enables an endless variety of tonal possibilities from ultra clean to crushing distortion and at any Level control setting Operates with 9V battery, PAD-1 AC adapter optional