Straight Edge, Flatness Tolerance +/- 0.0004 in, Calibration Certificate Not Certified, Parallelism Tolerance +/- 0.0002 in/ft, Thickness 0.22 in, Edge Style Square, Finish Polished, System of Measurement Metric/SAE, Features Marked With Arrows at Two Suspension Points, Quick Reading, Length - SAE 48 in, Length - Metric 1,219 mm, Width - SAE 1 7/16 in, Width - Metric 60 mm, Material Steel