Pre-mixed, ready-to-use high temperature silicates. Multi purpose cements for bonding and sealing both masonry and metals with working temperatures up to 2000°F. Designed for patching or reparing cracked or chipped firebrick and mortar. Effective in re-setting and cementing furnaces, stoves, chimney collars, boilers and duct work. Not suited for outdoor use. Cure time: 24 hrs at least 60°F. Paintable after fullly cured