I can't remember what they are called but the supports under the posts are bad.I removed one from under a post and it looks like it is cut from a two by four.It is 9 3/4 wide by 2 1/2 deep and cut on 45 degree on each end.Naturally four are cut on each post.I have tried to cut the same on my miter saw,but can't seem to get them where they form a square.Could I possibly use a piece a piece of concrete block the same thickness or treated 2x12 or 2x10.