GRK FIN/Trim Screws are an excellent choice for most fine carpentry applications, as well as window extension jambs, joining cabinets, and more. A combination of the smallest screw head available and code-approved structural performance means the most secure, concealed fastening in the industry. FIN/Trim Screws have a Climatek Coating for installation in both interior and exterior conditions where exposure to moisture is intermittent and is code-approved for use in treated lumber.