X-shooter spectrum of 2MASS J15491331 (in black) compared with photometric fluxes (light blue dots) from the Gaia DR2 and 2MASS catalogues. Synthetic fluxes derived from the observed spectrum are shown as red squares. The lines show a BT-Settl model of the same effective temperature as the target, for the two reddening values indicated in the labels. The model has been normalised to the flux of 2MASS J15491331 at 830 nm.