CheckBox ocultar y mostrar contraseña

Public Class Form1

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        TextBox1.Text = "esto es una prueba de UseSystemPasswordChar"
        TextBox1.UseSystemPasswordChar = True
    End Sub

    Private Sub CheckBox1_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged
        If CheckBox1.Checked Then
            TextBox1.UseSystemPasswordChar = False
        Else
            TextBox1.UseSystemPasswordChar = True
        End If
    End Sub
End Class