Sennelier - Universal Medium - 250ml Bottle - Sennelier Universal Medium has the same properties as the Turner paint medium, but it is produced using a synthetic base. Clear, gloss ketone resin based liquid medium, gives a highbuild finish and allows glazing and paint by accelerating drying. Universal medium improves the tones by adding bright and glossy appearance. Sennelier Universal Medium reinforces the mechanical properties of the finish and can be mixed with colors in any proportion. It can be diluted in petroleum spirit, turpentine and odor free spirits.