Needle punched, insulating material ideal for home sewers and crafters. Create projects like pot holders, oven mitts, and casserole covers. Hollow, polyester fibers needlepunched through a nonwoven substrate and through a reflective metalized poly film. This reflective material resists radiant energy, reflecting the hot or cold back to its source. Breathable and won't break down with washing. Heat resistant, not heat proof.