This heat-resistant, light weight ceramic impregnated paper, provides excellent separation between kiln shelf and glass in kiln firing applications up to 1500°F. ThinFire has numerous benefits when compared to more conventional ceramic fiber materials: Glossier back (shelf side) surface Greatly reduced binder burnout odors Lighter weight for easier handling and storage One time use only. Compared to conventional kiln washes, ThinFire reduces shelf preparation time and improves surface release quality. A single layer of paper will prevent molten glass from sticking to your shelf at full fusing temperatures (1450°-1550°F). ThinFire has been used with excellent results in Bullseye’s studio for many types of fusing applications. However, it does not work in every application. Used in direct contact with iridized glass, for example, ThinFire may cause a reaction resulting in surface pitting. We dont recommend using ThinFire under multiple small pieces of glass because the paper can shrink and move, disrupting the glass placement on the kiln shelf. Use shelf primer instead. Under very large or heavy pieces, ThinFire can rip, leaving a faint outline on the bottom of the piece.