Liquitex 237ml - Ultra Matte Medium 

Increases the volume of paint, while maintaining the opacity of the colour it is mixed into. Economically doubles the volume of paint by adding up to an equal amount (50%) of medium to colour with little or no noticeable loss in opacity or change in hue. The opacity of colours mixed with Liquitex Ultra Matte Medium will be higher than if the colour had been thinned to the same degree with any other medium except Modeling Paste. The degree to which the colour can be extended will vary among the different pigments. When over 50% is added, Liquitex Ultra Matte Medium can act as a weak tinting white, increasing the value of the original colour approximately one level. Light colours will be affected less than dark colours. Colours mixed with Liquitex Ultra Matte Medium-dry to a matte finish.