Carbon Steel Disc, Material Carbon Steel, Material Grade 1045, Overall Length 1 in, Heat Treatable Heat Treatable, Heat Treatment No Heat Treatment, Mechanical Finish Mill, Outside Diameter 4 in, Outside Diameter Tolerance 0 in/-0.005 in, Yield Strength 77,000 psi, Fabrication Cold Rolled, Rockwell Hardness Not Rated, Brinell Hardness 90 BHN, Tensile Strength 110,000 psi, Machinability 64 Percent, Length Tolerance +/-0.125 in, Includes Material Certificate Material Certificate with Lot Number