Great big outdoor storage deck box with a flat top.  We have 13 large cushions to store and about 10 of them fit.  As far as the double wall construction - I am not seeing this in the design, but it does seem sturdy.  It takes 2 people to assemble - some of the locking pieces are big and difficult to handle alone.  We ordered the light brown box, which really looks like on the website, but it really isn't light at all, it's dark brown. Let's see how it preforms after one summer in the desert...