GOLDEN OPEN Thinner is a water-based additive designed to thin the consistency of OPEN Acrylics without altering open time, as well as maintain and adjust the workability of colours on the palette. OPEN Thinner can also function as a thin-bodied retarder when used with GOLDEN Heavy Body or Fluid Acrylics. OPEN Thinner contains no binders, does not form a film, and should never be used alone.