Bracketron's Nav-Mat Portable GPS Dash Mount is highly convenient and works with both smartphones and many handheld GPS units. The Nav-Mat combines the physics of weight distribution with a high-tech, anti-skid material to provide a solid mounting base for your window-mounted device. Nav-Mat contours to the top of your vehicle's dashboard and works on any uneven or textured surface. The weighted anti-skid base keeps your device from sliding. Designed to work with the factory windshield mount sold with most smartphone or GPS units, this non slip dash mat for car requires no tools for installation and can easily be moved from vehicle to vehicle--or put out of sight when exiting the vehicle! It also works well with other Bracketron windshield mounts for mounting other devices such as satellite radio and MP3 players.