This premixed, easy to trowel, fiber reinforced refractory cement is an ideal high-heat sealant for masonry joints 1/4 or less. Use this cement to set, bond, and repair cracked or broken firebricks in stoves, fireplaces, and furnaces as well as for building fireplace boxes. Thick, smooth consistency makes this cement amazing for mortar between firebricks. Rated to up to 2000 degrees Fahrenheit. Rated up to 2000°F (1090°C)Requires heat to cure. May be painted once heat cured.For indoor useMeets ASTM E136 and E72Tub contains 64 fluid ounces