Contours are often used to present surfaces in 2D environments such as plans.
Surface
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Contours
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The Contour Layer tool will generate contour lines on any surface entities on the selected layer.
Right-click the layer to contour and click the Contour Layer button:

Set the interval between lines and click OK:

Min. Elevation
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Sets the minimum elevation that contours will be created.
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Max. Elevation
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Sets the maximum elevation that contours will be created.
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Interval
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Sets the vertical spacing between contours.
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Lines will be created and added to a new model layer named after the original layer with the interval appended (i.e. Hole Depth - Contours - 0.10):

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