With the magnet parallel to the reed switch the three lobes are present showing the generated arrays of magnetic sensitivity. The magnet is positioned within the pull-in lobe, so that ordinarily this position would close the contacts; however, in this case a magnetic shunt is positioned between the magnet and the reed switch. The magnetic shunt is comprised of a ferromagnetic material – nickel, iron or cobalt. In this case, the magnetic sensitivity lobes remain the same, but the magnetic flux lines emanating from the magnet travel almost entirely within the magnetic shunt instead of through the reed switch. Without the magnetic flux lines traveling through the reed switch, the contacts will remain open.