Temperature calibration for stars with CO absorption. For CO EW larger than −21.5 Å, the equations of Mármol-Queraltó et al. (2008) are used. These equations use our [Fe/H] determination. Below −22.5 the calibration by Feldmeier-Krause et al. (2017), corrected for the offset between the two, is used. Between these values (indicated by the two black lines) there is a linear transition between the two relations. The diagonal strip shows the uncorrected relation by Feldmeier-Krause et al. (2017). It is plotted for |[Fe/H]| < 0.075. The color scales saturate outside of 2600 K and 5800 K. The dots show our KMOS targets with S/N > 30.