Smooth-On URE-FIL™ fillers disperse easily in Smooth-On materials. They can be added to materials in different proportions to achieve a variety of working properties and effects. Some fillers are designed for cost-savings, others are designed for specific casting effects or improved physical properties. Other URE-FIL™ fillers are designed specifically for thickening materials for brush-on or trowelable application.

URE-FIL™ 11 is a fiber-based filler that can be added to Smooth-On urethane and silicone rubbers, urethane plastics and epoxies to thicken for brush-on applications. URE-FIL™ 11 can be used with all Smooth-On silicones, including those which do not respond to THI‑VEX™ such as Mold Max™ 40 and 60.