Made from pallets. It's my first project and pretty impressed that it fit. I had never used a saw before and almost made up whatever I didn't know, which was pretty much everything. With determination, I measured my door and framed it. Then I filled it with long pallet boards. I know now why you are supposed to bevel and joint the boards. No matter how hard you try, there is no way to keep from having holes. I don't know how to join boards, so I used clear caulking, glue and sealant to fill the holes.