The door does not fit an 80 inch opening even though the manufacturer is stating it does.  No one can but a 77 inch bi-fold door into an 80 inch height.  I am not satisfied with the product.  I had to add two inches of a wood plank filler and re-drill the holes to accommodate the door.  Fortunately I am capable of working with wood and was able to make it work, but that is NOT what I expected to have to do in order to hang the door.  I give this product an "F".