Our post base trim is for The Big Kahuna, The Sombrero, and The Fedora pergola kits and is intended to provide a decorative cover over post base mounting hardware. The trim will be made to match your wood choice and will measure approximately 1″ thick by 8″ high. The trim will be delivered assembled, so that it will slide easily onto the posts during your installation. Depending upon the actual measurements of the posts that come with your kit, the trim may fit more or less loosely around the base of the post. If you would like to secure the trim more tightly to the post and fill-in the gap at the top of the trim, we recommend that you purchase and apply a natural wood putty (or you could use caulk) at the top of the trim between the trim and the post.