Almatis FlameGard ATH (aluminum trihydroxide) is an inorganic hydrated alumina designed for use in polymer systems as a flame retardant and smoke supressive additive. FlameGard is more accurately designated chemically as aluminum trihydroxide, Al(OH)3, and is produced through processing of alumina-bearing feedstocks. Although FlameGard is a dry powder, when heated above approximately 220°C it decomposes into approximately 35% water and 65% alumina by weight. FlameGard is a nonabrasive, low density material with a Mohs hardness index of 2.5 - 3.5 and a specific gravity of 2.42. Almatis FlameGard ATH is compatible with polymer systems.