These double (or triple?) layered patio umbrellas solve a problem that I've had with the umbrellas that only have the small layer at the top... Wind!  The multi-layer umbrellas have more ways to allow wind to escape through the umbrella without lifting it away like Mary Poppins.  When it's breezy outside, I simply lower the umbrella a tad, thereby giving the breeze more ways to escape. And of course, they look lovely, too!  I won't buy anything but the multi-layered patio umbrellas again. Highly recommend!