Tool Steel Square Bar H13 offers high toughness and very good stability during heat treatment. H-13 tool steel provides good wear resistance in hot and cold work tooling. H13 exhibits a combination of shock resistance, red hardness, abrasion resistance, and is capable of withstanding rapid cooling. The bar is precision ground to a maximum surface finish of 40 Ra on both the thickness and width. Also, the bar is mechanically straightened with a flatness aim of 0.005" per foot.