JackRazz, to prove that this is possible, I've extended the Timer
component to include an automatic shutoff after a certain number of
times called. Take a look to see how I did it.

Option Explicit On
Option Strict On

Imports System.ComponentModel
Imports System.Windows.Forms
Imports System.Timers

<ProvideProperty("AutoShutOff", GetType(Timers.Timer)), _
 ProvideProperty("ShutOffValue", GetType(Timers.Timer))> _
Public Class TimerExtender
    Inherits System.ComponentModel.Component
    Implements IExtenderProvider

    Friend ht As New Hashtable()
    Dim value As Integer
#Region " Component Designer generated code "

    Public Sub New(ByVal Container As System.ComponentModel.IContainer)
        MyClass.New()

        'Required for Windows.Forms Class Composition Designer support
        Container.Add(Me)
    End Sub

    Public Sub New()
        MyBase.New()

        'This call is required by the Component Designer.
        InitializeComponent()

        'Add any initialization after the InitializeComponent() call

    End Sub

    'Component overrides dispose to clean up the component list.
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

    'Required by the Component Designer
    Private components As System.ComponentModel.IContainer

    'NOTE: The following procedure is required by the Component Designer
    'It can be modified using the Component Designer.
    'Do not modify it using the code editor.
    <System.Diagnostics.DebuggerStepThrough()> Private Sub
InitializeComponent()
        components = New System.ComponentModel.Container()
    End Sub

#End Region

    Public Function CanExtend(ByVal extendee As Object) As Boolean
Implements System.ComponentModel.IExtenderProvider.CanExtend

        If TypeOf extendee Is Timers.Timer Then
            AddPropertyValue(DirectCast(extendee, Timers.Timer))
            Return True
        Else
            Return False
        End If

    End Function

    Private Function AddPropertyValue(ByVal ctrl As Timers.Timer) As
TimerExtendedProperties

        If ht.Contains(ctrl) Then
            Return CType(ht(ctrl), TimerExtendedProperties)
        Else
            Dim tbProperties As New TimerExtendedProperties()

            ht.Add(ctrl, tbProperties)

            AddHandler ctrl.Elapsed, AddressOf TimerElapsed

            Return tbProperties

        End If

    End Function

    Private Sub TimerElapsed(ByVal sender As System.Object, ByVal e As
System.Timers.ElapsedEventArgs)

        Dim ctrl As Timers.Timer = CType(sender, Timers.Timer)

        value += 1

        If value >= GetShutOffValue(ctrl) Then
            ctrl.Enabled = False
            value = 0
        End If

    End Sub

    <Description("Enable automatic shutoff?"), _
     DefaultValue(False)> _
   Public Function GetAutoShutOff(ByVal ctrl As Timers.Timer) As Boolean

        If ht.Contains(ctrl) Then
            Return CType(ht(ctrl), TimerExtendedProperties).enabled
        Else
            Return False
        End If

    End Function

    Public Sub SetAutoShutOff(ByVal ctrl As Timers.Timer, ByVal value
As Boolean)
        AddPropertyValue(ctrl).enabled = value
    End Sub

    <Description("Value of when to shutoff timer."), _
      DefaultValue(1)> _
   Public Function GetShutOffValue(ByVal ctrl As Timers.Timer)As Integer

        If ht.Contains(ctrl) Then
            Return CType(ht(ctrl), TimerExtendedProperties).count
        Else
            Return 0
        End If

    End Function

    Public Sub SetShutOffValue(ByVal ctrl As Timers.Timer, ByVal value
As Integer)
        AddPropertyValue(ctrl).count = value
    End Sub

End Class

Public Class TimerExtendedProperties
    Public enabled As Boolean = False
    Public count As Integer = 1
End Class