The Setasilk Water Based colorless Gutta has a thick consistency and is used to create outlines - the Serti technique. The Colorless Gutta is used directly from the tube and nozzle or from a pipette and Gutta nib. It flows readily into the silk fibers forming a barrier to the color. Setasilk is applied afterwards. The colorless Water Based Guttas designed to wash out leaving a white line on the fabric where it has been applied.