Presets for given Analytical Extension. 
   Namespace:   Autodesk.Revit.DB.Structure  
  Assembly:   RevitAPI  (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0) 
Syntax
| C# | 
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| Visual Basic | 
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| Visual C++ | 
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Members
| Member name | Description | 
|---|---|
| BottomOrTop | Bottom or Top of physical element. | 
| Plane | Use a Plane for extension (e.g., Grid, Level). |