Post base trim is a trim molding for the base of a post. Post base trim is available in 4” x 4” and 6” x 6” sizes, three styles, and three wood species: pressure-treated pine, cedar and redwood. Our post base trim is cut to size, with three sides pre-joined. The fourth side can be easily slipped into place and attached with finish nails, staples or exterior-grade construction adhesive.