for the Navi offers this article. Once installed holds the Navi bombproof (with me a Navi Becker) and the view through the windshield is hardly restricted. And a small hook to secure the beanbags on the shelf must only be stuck, not a plate of about 10 cm in diameter; Seems simple nicer if the beanbag is not just in use. The only drawback: the beanbag already requires some space in the glove compartment when unhooking it when leaving the car, so as not equal to signal the presence of a curious contemporaries Navis.
