As you digitize line features with containers, the containment relationship is established automatically.
You can later change the containment relationship on Quick Info or the Feature Info palette on the Dashboard.
Palettes panel
Dashboard
Feature Info.
In the following example, we select an underground segment that contains a duct, and the duct contains a conductor.
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Click the feature to add.

The button "Add features to this container" for a line container (e.g. a segment) allows selection of features from adjacent sections. Choosing a line will contain it to the selected segment. This can be used to reroute a line.
For example, a conductor is in the duct connecting vault 1 to vault 2, and you can follow the steps below to reroute it to the duct connecting vault 1 to vault 3.

Palettes panel
Dashboard
Feature Info.
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Now the conductor is not in any duct.

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Click the blue dot before the conductor.

Now the conductor is in the duct connecting vault 1 to vault 3, and the geometry follows the duct.
