Andoer Electric Guitar Effect Pedal Mini Single Effect with True Bypass (Dyna Compressor) Lightweight, portable and big sound. Based on the MXR dyna compressor. Single knob control to adjust the degree of compressor sensitivity Run a cable from your guitar to the Dyna Comp's input jack and run another cable from the Dyna Comp output jack to your amplifier. The light flashing when working. True bypass in order to protect signal integrity when the pedal is not engaged. Foot-switch toggle controlling on/off condition.