adjustable square

tool

Also known as: bevel square

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Last updated

July 23, 2026

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An adjustable square, also known as a double square, is a measuring tool used to check for correct right angles. It features a sliding connection between its arms, allowing it to form both a T and an L shape. This tool is valuable for carpenters and machinists, serving as a guide for drawing lines before cutting and for verifying right angles. A related tool, the combination square, includes a steel rule with attachments like a protractor and a center head, expanding its utility for various measuring and marking tasks.1234

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hand tool
Plumb line, level, and square
The adjustable, or bevel, square was used for angles other than 90 degrees beginning in the 17th century. In the earliest examples, the thin blade moved stiffly because it was riveted into a slot in the thick blade. Later models of the 19th century, however, were…
Read More
The adjustable, or bevel, square was used for angles other than 90 degrees beginning in the 17th century. In the earliest examples, the thin blade moved stiffly because it was riveted into a slot in the thick blade. Later models of the 19th century, however, were…
Read More