Observed-frame optical spectra obtained with Subaru/FOCAS and HET/LRS2 of the M-dwarf sample. The best-fitting template spectra (from PyHammer; Roulston et al. 2020) are shown in blue with the M-dwarf type indicated in the top left of each panel. We have binned each spectrum to reduce the noise level and enable a qualitative assessment of the template fits. All spectra are publicly available at the CDS.