This thing was dirt cheap, it opens easily and collapses to a VERY compact size which fits in my door map pocket, and fits my windshield extremely well with minimal gap. The top surface is not entirely flat when open, it's concave, which I think might be an intentional design to compensate for the rearview mirror being in the way. It needs the visors to hold it in place, it won't stay up without them. My only complaint is that straight out of the pouch it had a terrible odor, like a dead fish! I suggest you do what I did, open it and Febreze the fabric surfaces thoroughly front and back, and let it dry a long while. Now every time I install it in the windshield it creates a nice aroma in the car.