The screen visor is designed to block off unwanted sun light from the top and sides of the screen. * It will reduce glare and reflections for better contrast and visibility. * The screen visor is light weight and can be attached to virtually any personal navigation devices. * The visor can be extended to accommodate 3.5 inch ~ 7 inch screen GPS. * Adjustable Visor for Garmin Nuvi, Mio, Magellan and TomTom Navigation Devices with 3.5" ~ 7" screen