Parallel ruler
A parallel ruler is an aid and drawing device that enables you to draw or define a line to an existing one at the same distance (parallel).
It consists of two individual rulers , which are connected by (mostly) two, also parallel and rotatable rails so that a parallelogram is created. Divisions and angles can be indicated on the rulers.
The parallel ruler is often used for nautical cutlery . The use of this drawing device is particularly widespread in the Anglo-American region. The advantage is the very space-saving design from a single part. The disadvantage are less accuracy and less displacement compared to the use of course triangle and Abschiebedreieck .
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