A classroom classic, this 12" long wood ruler has a clear lacquer finish. Single metal edge. Scaled in 1/16" on one side and metric on the other. Ruler Type: Standard/Metric Length: 12 in Standard Scale: 1/16 in Metric Scale: Centimeters Millimeters.ACM10377. 10377. Westcott Westcott Wood School Ruler w/Single Metal Edge.