The model of a foot pedal to make your own sustain pad or guitar patch changer with the addition of a few wires. Fit a pen spring between the hooks in the center of the pads. place them facing each other. Put two screws into the holes at the edges of the pads and take the electric leads from there. Use a wire or needle through the hinge and twist/seal it in place. for more info: youtube.com/lyle963