Pebeo Superfine Gouache Varnish - 400 ML is based on a non-yellowing acrylic that enhances the sheen of gouache colours. The varnish will protect the work and give a uniform finish; holds well on the brush and adds a strong brilliance and durability to even poorer works. Must be applied to completely dried works; dries rapidly in about 2 to 3 hours depending on the thickness and the temperature.