It's a complete pedal for your bass. Look at this brief description and you'll realize that you can't live without this pedal: 2 channels (Clean and Drive) that can be changed in a single step; Independent Bass, Mid and Treble control; Volume controls for each channel, so you can set each channel with its gain; 3-position treble adjustment switch for the Drive channel; The Drive channel also has a Drive addition control in addition to the volume control.; P10 Input and Output, but if you need to plug it directly into the desk or audio interface you can use the Balanced XLR output; Ground Lift button to eliminate squeaking.