Tube distortion simulation. FET transistor inside. High gain. Low power consumption. Ultra low noise operation amplifier inside. The effect has got ture bypass. When your turn off the pedal, the original sound is perfectly output without any distortion. Specifications: Input Impedance: 500k ohm; Output Impedance: 150 ohm; Recommended Load Impedance: 10k ohm; Equivalent Input Noise: -90dBu or less; Power Supply: DC 9V-battery or AC adapter; Current Draw: 5.7mA (DC 9V)