The M-117R effects pedal has 4 knobs and a footswitch. The footswitch toggles the flanger effect on/bypass (red LED indicates on). The Manual knob selects the frequency center of the effect when auto-sweep is disengaged.
The Width knob at zero disengages auto-sweep, but when you rotate it clockwise, it increases the total phase sweep of the effect. The Speed knob modulates rate of effect. The Regen knob feeds the effect back onto itself at adjustable intensity, increasing the total phase effect.