See how tool materials and designs have changed over the years as experts compare tape measures, squares, bevels and more.
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Some Nineteenth century American tri-square had rosewood stock and brass escutcheon braced the blade in place. Contrast that with the modern cast aluminum speed square. It has a lip that registers against the piece you're measuring to hold it in place while you mark off 90 or 45 degree angles. The yellow plastic triangle in the center, folds up for portability.
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