This .NET class wraps the AcDbFcf ObjectARX class. 

Feature Control Frames for Geometric Dimensioning and Tolerancing are the entity type created by the TOLERANCE command in the AutoCAD command editor. Tolerances are considered as dimensions in AutoCAD, which means they are controlled by dimension variable settings and dimension styles. 

Within objects of this class, the text string data member contains symbol and format codes that are used to define the actual graphical representation that will be seen within AutoCAD. For more information on these control codes, see the FeatureControlFrame.SetText() member function description.

Autodesk.AutoCAD.DatabaseServices.DBObject
    Autodesk.AutoCAD.DatabaseServices.Entity
        Autodesk.AutoCAD.DatabaseServices.FeatureControlFrame

Public Class FeatureControlFrame
Inherits Entity

public class FeatureControlFrame : Entity;

This class overrides Entity.SubSetDatabaseDefaults() to set the object's dimension style (dimstyle) to the current style for the database. Typically, objects of this class are initialized with a call to SetDatabaseDefaults() followed by a call to SetDimstyleData() using data obtained by a call to Database.GetDimstyleData().

DBObject, Vector3d, Point3d, Point3dArray