Energy spectrum of PG 1553+113 obtained from the H.E.S.S. II mono analysis (blue) corrected for EBL absorption in comparison with the contemporaneous Fermi-LAT data with a minimal energy of 0.1 GeV (red). The assumed redshift is z = 0.49. The black line is the best-fit log-parabola model fit to the points and the cyan butterfly indicates the 1σ (statistical error only) uncertainty region. The right-hand y-axis shows the equivalent isotropic luminosity (not beaming corrected).