This .NET class wraps the AcDbMInsertBlock ObjectARX class. 

The MInsertBlock class represents a special form of the INSERT entity in which an array of duplicate images of the entities within the referenced BlockTableRecord is displayed. 

Creating an MInsertBlock with a definition of rows = 1 and columns = 1 will create a BlockReference instead.

Autodesk.AutoCAD.DatabaseServices.DBObject
    Autodesk.AutoCAD.DatabaseServices.Entity
        Autodesk.AutoCAD.DatabaseServices.BlockReference
            Autodesk.AutoCAD.DatabaseServices.MInsertBlock

Public Class MInsertBlock
Inherits BlockReference

public class MInsertBlock : BlockReference;

The number of rows and columns of images to display can be set, as is the spacing between the rows and columns. 

Do not derive from this class. Attempting to do so will cause your application to halt AutoCAD.

DBObject, Entity, BlockTableRecord