Lifesavers Intelligent Speed Assistant (ISA) utilizes GPS technology to identify speed limits on the roads your teen is driving and syncs with the vehicle to prevent speeding. If the driver attempts to go above the speed limit, the pedal will not respond to the attempted increase, ensuring the driver and others remain safe. You can pre-program a set tolerance above the speed limit, such as give miles per hour, to suit your family's needs. Free Professional installation included.