Acrylic Mediums by Liquitex
Intended to reduce the viscosity of acrylic paint, fluid mediums by Liquitex are a great way to adjust the thickness of and application properties of a paint directly out of the tube. When mixed with paint from a tube or jar, they extend the paint, increase transparency and adjust sheen.
Liquitex offers matte mediums and gloss mediums, mixes and dries transparent and can be used as fixative or ground.
A video by Michele Theberge about the properties of Liquitex Mediums: