Placed between the hydraulic block and the clutch cylinder, the clutch re-engagement control gives a progressive engagement and a fast disengagement.
Disengagement - the fluid under pressure arriving at the clutch cylinder is not slowed. Fast disengagement
Engagement/Re-engagement - a lever controlled by the accelerator pedal determines the speed of engagement and re-engagement by the obstruction of the fluid flow (ball more or less seated).
The re-engagement will be faster since the driver will desire acceleration or a higher gear: accelerator pedal pushed.
When there is no action on the accelerator pedal, liquid under pressure contained in the clutch cylinder passes by the ball of obstruction (via indents made on the ball's seat).