Dalas Artist masking Fluid is a colour block medium for oil, acrylic and watercolour. It is an off white elastic gum solution, that will darken slightly when dry. The colour block technique is used to acheive contrast and lighting effects. Apply a coat of Artists' Masking Fluid to an area where you would like the colour to be blocked. Several coats can be applied for a stronger film strength, especially when working on a large scale. Ensure that the previous coat has dried thoroughly before applying the next coat (Product will darken slightly when dried). Apply oil, acrylic or watercolour liberally once the masking fluid has dried. Once the paint has dried remove the dried masking fluid by gently lifting and peeling, or rubbing it away with an eraser. *Clean brushes immediately after use with hot, soapy water PLEASE NOTE: Do not shake bottle