Phase averaged photon spectra of the neutron star models with parameters kT_p1 = kT_p2 = 0.15 keV, B_p1 = B_p2 = 6 × 10¹³ G, i = θ_B = 0° and a = 0.25. The local spectra are from a naked iron surface, computed accurately using the code presented by van Adelsberg et al. (2005) (thick solid curve), and using approximate Eqs. (8)–(12) (thick dashed curve). The adopted continuum spectra without absorption features are shown by the corresponding thin curves. The EWs of the absorption features are rather similar,  ≈ 190 and 180 eV.