The brake servo reduces the force you need to put on the brake pedal.
The two-stage brake servo represents an innovation. Up to a brake pressure of about 45 bars, known as the comfort braking range, the brake servo operates with a strengthening of factor 5. If the driver steps harder on the brake, this braking force increases up to factor 10.
The driver notices this through a faster braking behaviour on the short pedal, as well as good control and reduced braking effort, up to the point where the ABS is activated.