The active roll-over protection system is located behind the rear head restraints. It works with the reinforced windscreen frame to provide extra crash protection for the car's occupants. The system contains sensors that monitor the car's progress. If they detect the risk of a rollover or impact, a dual-lever release system automatically turns the rear head restraints into a pair of robust rollover bars. These bars are housed in special cassettes bolted to the luggage compartment wall behind the rear seats. Once activated, they shoot upwards and are securely locked into place within 250 milliseconds.