Thixo additive transforms liquid silicone into nonflowable thixotropic paste (no runs, no drips). Very useful for vertical molds, ceiling reliefs or figures with irregular surface saliences; designed for Brush-On (brush-up) mold technique. Adds between 1-3% by weight an both types of silicones. With addition cure (platinum) silicones up to 20mm thickness and with condensation cure (tin cure) silicones up to 5mm thickness per coat.