Model Wash paints are liquid, transparent paints designed to create aging and weathering effects on armor, vehicles, aircraft, ships, figures and other miniatures and models, as well as on dioramas. All surfaces exposed to the sun, wind and dust or rain and snow will experience a change in hue: a loss of intensity, dulling and general fading. For the painter of models these changes are difficult to reproduce. To achieve these effects, "washes" are the perfect solution.

Washes can be mixed together to create further variations of colour tones; they can be applied with an airbrush or with a brush - depending on the requirements and the desired effect. Washes are also very suitable for delineating the edges of tare colours to the base colour of a model. They can also be mixed with pigments or acrylics to create a wide range of effects such as oil, rust, mud, earth, dust, moss, etc.

Vallejo Wash paints have been formulated with an acrylic resin so that the surface tension is similar to traditional solvent-based washes and filters, but with the advantages of a water-based medium. The average drying time of wash paints is approximately 20 minutes. If multiple coats are to be applied, it is best to wait about 40 minutes between applications. Painting utensils are to be cleaned with water.