Get MAC Address of Windows Machine in C#

 Dim mo As ManagementObject
        mc = New ManagementClass("Win32_NetworkAdapterConfiguration")
        Dim moc As ManagementObjectCollection = mc.GetInstances()
        For Each mo In moc
            If mo.Item("IPEnabled") = True Then
                mackey = mo.Item("MacAddress").ToString()
            End If

        Next

i have the ABOVE CODE 

but i am not getting the mac address