Metal planter box. This is 2, 12 inch tall boxes that I stacked and screwed together. These are not "stackable" in the sense you cannot just set one on top of the other without fasteners. Didn't realize this when purchased so I used metal plates and screws to accomplish desired height. You could remove hardware to have 2 seperate boxes if you wanted. The corner braces I upgraded to galvanized bolts. Text only.