12 Inch Architect/Engineer /Metric Triangular Scale Ruler

12 Inch Metric Triangular Scale Ruler. Made from solid aluminum. Three Sides With Six Different Scales. For Professional Applications, Architecture, Engineering, And Technical Drawing. These triangular multi-scale rulers are ideal for architects, draughtsmen, students and artists. Each ruler has different scales "Metric" (mars98719-SI Metric) 1:5, 1:50, 1:1, 1:10, 1:20, 1:2 "Engineer" (Mars 987 19-34) 10, 50, 60, 30, 40, 20 "Architect" (Mars 987;19-31) 3/32, 16, 1 & 1/2, 3, 1/8, 1/4, white unnamed 1, 1/2, 1/4, 1/8, 16, 3/32, 1 & 1/2, 3, 3/8, 3/4, 1/2, 1/8, 1/4, 1, 16, 3/16, 3/32