10.3 oz. Buff & Mortar Cartridge. Designed for repairing cracked and chipped firebrick, as well as tuck pointing mortar into damaged masonry-to-masonry joints where cracks are 1/4 inch or less. This non-asbestos cartridge offers great bonding strength and durability, comparable to firebrick when heat cured. It withstands temperatures up to 1,093 °C (2,000 °F) and meets the TM136-79 flammability test.