A2 Precision Ground Tool Steel Square Bar is ground to a maximum surface finish of 40 Ra with tolerances of +/- 0.001” on the height and width of the bar. This material is produced from cross-rolled sheet or plate which produces a finer grain size and enhances the toughness of the material. Lastly, tool steel rectangle bar is 100% free of decarburization is completely spheroidized throughout. and mechanically straightened with a flatness aim of 0.005" per foot.