Spectral fits of the B (left panel) and C (right panel) companions to the old population (∼10 Myr) of standard spectra from Luhman et al. (2017). Our companions have been corrected for reddening assuming the same extinction as the primary star (see Sect. 3.1). To compute the χ² per degree of freedom, we refrain from using spectral regions affected by tellurics. The panels on the right of each B and C comparison is an H-band zoom-in, which is more affected by the gravity of the object.