207 Special Clear Hardener® was developed for coating and fiberglass cloth application where an exceptionally clear, moisture-resistant, carbon fiber or natural wood finish is desired. 207 Special Clear Hardener will not blush or turn cloudy in humid conditions. Thin film applications roll out and tip off smoothly, requiring less sanding in preparation for finish coatings. The mix ratio is 3 parts resin to 1 part hardener by volume.