Two examples of the disc magnetic field with radial reversals. Top panels: field strength in the galactic mid-plane is shown colour coded with arrows showing the direction and strength of the magnetic field projected onto the mid-plane. Model A, shown in (panel a), has a reversal at s = 7 kpc and corresponds to the same field as in the bottom right panel of Fig. 5. Model B, shown in (panel b), has the same parameters except for having two reversals at s = 7 and 12 kpc. Panel c: azimuthal magnetic field in the two models. Panel d: vertical cross-section of Model B is shown, with the magnitude of azimuthal magnetic field indicated with colour and arrows showing the projection of the magnetic field onto the (xz)-plane.