Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Furnishings and Equipment (hierarchy name)
4. Measuring Devices (hierarchy name)
5. measuring devices (instruments)
6. [measuring devices for extent]
7. distance measuring devices
8. linear distance measuring devices
9. rulers (measuring devices)

Anotations

Scope note:

Describes a pair of rulers connected by two pivoting cross pieces of equal length set so that the rulers always remain parallel to each other; used as navigational tools for transferring parallel lines. For drafting tools used to draw parallel lines and affixed to and guided along drafting boards, use "parallel rules."