This 12-inch-by-12-inch heat resistant work surface is made from insulation material and is a perfect work surface for soldering copper-foiled stained glass. Ample space for small stained glass projects with room to spread-out tools and equipment. 1/2-inch thick. Perfect for small projects Solder copper-foiled projects Made from insulation material 1/2-inch thick 12-inch by 12-inch surface