MagneticNumbers create competition numbers for use on Sprint and Race Cars.These are especically useful for the grass-roots motorsports level where competition numbers are defined on a per-event basis and so the numbers need to be changed every event.Also forArrive-and-Drive eventswhere the competition vehicle is driven to the event, it is illegal to display competiton numbers on a vehicle on public roads unless the vehicle is actually competing in an event, thus these can be fitted quickly and easily when you arrive at the event.