The power-assisted mechanism, which operates on the Dewandre system, trebles the driver's effort over the first half of the available range. Thereafter, the multiplying effect due to the mechanism is purposely reduced so that it is necessary for the driver to exert a deliberate effort in order to apply the maximum braking force: this is done in order to provide all automatic safeguard against and clumsiness. The great advantage of this system is that, being entirely free from any cumulative effect, it provides the driver with a direct and sensitive control.

It requires no special skill in operation and the extent to which it compensates for differences in physical strength is such as to enable ladies to drive even large cars safely at any speed. One of its greatest benefits is that it minimises the fatigue of long journeys, when the frequent use of the brake incidental to fast travelling otherwise becomes so tiring. With this system it is possible to drive all day without feeling the strain.