Great little sand box. We bought two for sand and gravel. One is filled with 12 bags 0.5 cu.ft pea gravel. The other is 12 bags 50lb play sand. They play for hours in these. The cover does fill with water in the middle so we invert a plastic bucket in each before covering. I didn’t do a great job leveling the spot so some sand does ooze a little out one side. But then they toss the sand around too so it’s bound to need refilling.