Straight Edge, Flatness Tolerance +/- 0.0003 in, Calibration Certificate Not Certified, Parallelism Tolerance +/- 0.0002 in/ft, Thickness 0.17 in, Edge Style Beveled, Finish Polished, System of Measurement Metric/SAE, Features Quick Reading, Length - SAE 18 in, Length - Metric 450 mm, Width - SAE 1 7/16 in, Width - Metric 36 mm, Material Steel