Winsor & Newton Artists' Oil Mediums allow you to alter the characteristics of your oil paints. Adjust consistency, gloss, drying rate or texture. Working with mediums while painting helps the Artist to not over-thin his/her paint. Varnishes provide a transparent coating which protects the finished painting from dirt. Picture varnishes are removable, enabling the painting to be cleaned in the future. Varnishes should not be used as mediums for adding to the colour. A UV resistant gloss varnish which gives temporary protection to recently completed oil paintings. Quick drying. Ensure painting is touch dry. Use thinly.