Features: 4 functional knobs(tone/gain/vol/boost) for adjusting the performance of the overdrive effect. 2 toggle switches for mode adjustment: one for hard clip/flat/smooth mode, and the other for mosfet clipper/diode clipper mode. Aluminum alloy metal shell, durable and sturdy, lightweight and compact. Mini compact size, portable and easy to operate. Equipped with a non slip silicone pad, easy to install, making the effect pedal non shifting and anti slip during performance. Specifications: Material: Aluminum alloy Input Impedance: 1M Output Impedance: 100 Running Current: 8mA Item Size: 108 * 69 * 32mm / 4.25 * 2.72 * 1.26in Item Weight: 279g / 9.86oz Package Weight: 323g / 11.40oz Package Size: 12.5 * 8 * 5.7cm / 4.92 * 3.15 * 2.24in Package List: 1 * Effect Pedal 1 * Silicone Pad 1 * Manual (English) Note: Please use a DC +9V power supply which is positive outside and negative to connect this unit and connect the input and output socket to this unit.