Tough metal and large enough to hold all cushions from my outdoor set.  Like the basket-weave design, am sure it will minimize the inevitable scratches to come.  

Just like previous reviews, I ended up replacing some of the screws.  Remaining issues for me are 
(1) no handles on the sides to assist in repositioning the storage box
(2) the box does not close squarely (perhaps there is a fix for this that I am unaware of...?) 
(3) optional wheels would be very useful!