High Density / Super Duty Hard Fireclay Bricks are a dry pressed, exhibits good strength, low shrinkage, excellent resistance to thermal shock conditions and a good resistance to alkali and carbon monoxide disintegration. Recommended for moderate to high heat, medium abrasion applications including boilers, furnaces, arches, floors and kiln fireboxes. Dimensions: 9" x 4.5" x 2.5".