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tokens: the spectra we used the multi-component approach of Kosenko et al. (2010) , who extensively studied the XMM-Newton and Chandra data. First, one NEI component with LMC abundances accounts for circumstellar medium (CSM) or ISM emission. Then, one NEI component for each (group of) element(s) having detected lines: oxygen, silicon and sulphur, argon and calcium, and iron. In the latter case two NEI components with distinct parameters are used, as the spectrum evidently includes both medium temperature and very hot iron. Due to the low count rate, and therefore statistical weight, of the Fe K blend, the hot iron component was driven to fit lower energy lines instead. To alleviate this issue we fitted the high-energy part of the spectrum separately with this component, then froze the best-fitting parameters in the global fits. Residuals around 0.72 keV (lines of Fe xvii ) were fitted with an additional Gaussian line. 0509<inline-formula specific-use="simple-math">−</inline-formula>67.5 (MCSNR J0509<inline-formula specific-use="simple-math">−</inline-formula>6731): XMM-Newton observed the SNR for ks in 2000, with pn operated in Large Window mode. This dataset is presented in Kosenko et al. (2008) , while Warren Hughes (2004) reported the spectral and imaging analysis of a Chandra observation. Finally, Badenes et al. (2008) attempted to reproduce spectra from both instruments using a grid of hydrodynamical models and an X-ray emission code. Inconsistencies between pn and MOS spectra were found, with lines in the pn spectrum (red-)shifted relative to those in MOS spectra by about 1%. This is likely a gain issue of the pn instrument. We discarded spectra from the MOS instruments, as they were operated in Small Window mode, for which no FWC data are available. To get the spectral model to match the observed energies of atomic lines, we freed the “redshift” parameter available in XSPEC models, which allows an ad hoc change of the energy scale. Satisfying results were obtained for a shift of 1%, which is the measured pn/MOS discrepancy Kosenko et al. (2008) . As for J05196902, lines from heavy elements are prominent, and we used a multi-component model. Si, S, and Ar were grouped in a NEI component, and shared the same temperature and ionisation age. Another NEI component modelled the continuum+lines emission from the CSM/ISM. No Si, S, Ar, or Ca were included in this component. Iron was included in two NEI components, one with a medium temperature (1.4 keV) and a high- one (11 keV) that reproduces the strong Fe K line. The latter component also includes calcium. Even with this model, residuals remained around Fe lines (0.72 keV and 1.22 keV), which we fitted with two Gaussian lines. The very high temperature of the second Fe component is atypical for SNRs, but was also suggested in Chandra data by Warren Hughes (2004) . The SNR exhibits a high-energy continuum tail, which previous studies tried to reproduce with non-thermal models. This tail can also