Engineers Rule Thickness 1.81 in Graduation Marks 1/100 ft 1/16 in Coating Abrasive Resistant Epoxy Graduation Color Red Flexibility Rigid Graduation Mark Style Etched Edge Style Not Applicable Orientation Vertical Folding Rule Type Outside Read Backing Material Not Applicable Finish Unfinished System of Measurement Metric/SAE Accuracy +/-1.4mm Rule Type Engineer s Rule Numeric Marks Inches Millimeters Numeric Format Fractional Length - SAE 6 ft Length - Metric 1 800 mm