12inch Triangular Architect Scale Designed To Facilitate The Drafting And Measuring Of Architectural Drawings, Such As Floor Plans, Blue Prints, And Orthographic Projections Triangular Ruler Made From Shatterproof High Impact Heavy Plastic Architect Ruler With Durable Imperial Prints For Accuracy. They Will Not Wipe Or Scratch Off Color Coded Triangular Scale For Easy And Quick Selection Of The Desired Scale Imperial Scale: 1-1/2, 1, 3/4, 3/8, 3/16, 3/32, 1/2, 1/4, 1/8, 3, 16