The Armstrong Ceiling Tile 1820A is a 2' x 2' lay-in ceiling tile made of mineral fiber. It has a fine texture and white matte finish. The tile has a CAC rating of 35 and NRC rating of 0.55. It meets ASTM E1264 classification for Type III, Form 2, Pattern C mineral fiber tiles. The tile is designed to install into a suspended grid system to create an attractive, durable ceiling. With its high light reflectance and acoustical properties, this tile is well-suited for use in commercial spaces like offices, retail stores, and schools. The tile carries a 10 year limited warranty.