Liquitex Professional Flexible Modeling Paste Medium, 8-oz 100% polymer emulsion that dries more slowly than other modeling pastes to a hard yet flexible surface Lightweight, non-toxic and increases thickness and rigidity Includes 8-oz / 237ml jar of medium Intermixable with Liquitex Professional Acrylic Paint Colors and Mediums. Conforms to ASTM D4236; Safe for educational use