8 OZ, Black, Furnace Cement, Pre-Mixed, Easy To Use, Especially Suited For Sealing Metal To Metal & Metal To Masonry Joints, Can Be Used On Cast Iron, Steel Or Firebrick, A Creamy Smooth Black Silicate Ceramic Type Cement, Durable As Firebrick When Heat Cured, Withstands Temperatures Up To 1093 Degrees Centimeter (2000 Degrees Fahrenheit).