A control in Autodesk Revit family document. 
   Namespace:   Autodesk.Revit.DB  
  Assembly:   RevitAPI  (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0) 
Syntax
Remarks
 The object represents a variety of different shapes of controls in family document. The different shapes of controls can handle the family instance in different ways. 
 - A vertical/horizontal arrow control rotates the instance by 180 degrees.
- A double vertical arrow control mirrors the instance geometry vertically.
- A double horizontal arrow control mirrors the instance geometry horizontally.