Spectragel Medium is a thixotropic alkyd medium designed to mix with oil colours, retaining the body of the paint. The word thixotropic means sometimes fluid and sometimes gel - this medium becomes fluid when stirred and returns to a gel state when allowed to stand. Quick drying and gives a glossy finish. It is a clear medium based on a synthetic resin that dries to a weather resistant and strong, resilient surface.  Ideal for glazing and extending colours while retaining gloss and structure of paint.