Protection of children as car occupants raises a major problem, as it is necessary to take into account two factors which are specific for them: their behaviour, which corresponds to a need for movement and their very fast growth. The most common restraint devices look like individual seats and are designed to protect young children, less than three years old. More recently, new restraint devices, called "cushions" were developed. They are designed for children of over three years until adult size and they are used with the adult belt; they generally enable some improvements in the location of the belt on the child body, so ensuring better protection. This paper presents a special cushion developed by Renault, the originality of which is that it is integrated in the rear bencha nd concealablew hen there is no child in the rear places. Dynamic tests were performed with a six year old child dummy at impact speed and deceleration law corresponding to those of licensing procedures; the performance of this cushion are described.