The footcontroller expands the functionality of the ID:Core amps. Features: Mode 1 - allows the user to switch between two channels and turn the effects on and off. Mode 2 - allows the user to switch between all the patches (down on switch one and up on switch two). Please note the FS-11 footcontroller can only be used with the ID:Core Stereo 20 and ID:Core Stereo 40.