Luminosity SEDs of a selection of SNRs for which the distance is well constrained and the γ-ray emission is likely dominated by hadronic emission. The Fermi-LAT data points are taken from the 4FGL DR2 catalog (Ajello et al. 2020) except for Kepler, where data from this work are used. TeV spectral data points for Cassiopeia A are taken from Abeysekara et al. (2020), from Archambault et al. (2017) for Tycho, from Prokhorov et al. (2021); H.E.S.S. Collaboration (2022) for Kepler, from Humensky & VERITAS Collaboration (2015) for IC 443, and from H.E.S.S. Collaboration (2018) for W44 (upper limit from the H.E.S.S. galactic plane survey). The references for the distances are given in the main text.