Polyurethane provides the toughest finish available. The three types of finishes available are Matte, Satin and Gloss. All varnishes have excellent brushing qualities and may be used inside or out to provide maximum, long term protection. These varnishes dry clear and are non-yellowing. They have excellent corrosion, chemical, scratch and wear resistance. A slight milky appearance may occur when applying Jo Sonja's Satin Varnish. This is normal and is more obvious on dark backgrounds. The milkiness should disappear as the varnish dries and cures. Sand lightly if 24 hours lapse between coats to ensure good adhesion. Apply at least 4 coats for maximum protection. As with most water based finishes, you can handle painted objects when they are dry to the touch, but maximum durability is not achieved until varnish reaches its cure time (at least 2 weeks under normal conditions).