4142 Alloy Steel Plate, Material Alloy Steel, Material Grade 4142, Heat Treatable Yes, Heat Treatment Pre-Hardened, Mechanical Finish Mill, Overall Length 18 in, Overall Width 10 in, Thickness 0.75 in, Thickness Tolerance +/-0.001 in, Yield Strength Not Rated, Fabrication Hot Rolled, Rockwell Hardness B94, Machinability 50 Percent, Tensile Strength Not Rated, Width Tolerance +0.005 in, Standards ASTM A322, Includes Material Certificate Yes, Appearance Metallic, Brinell Hardness 187, Shape Plate