NIR colour-magnitude relation with assigned 93 member galaxies. Light-grey points are all galaxies from the optical and NIR catalogues. The blue solid line is the best fit for spectroscopic cluster members as in Figure 2, with orange lines showing the 2.5 sigma limits. The red open circles have quenched galaxy spectra (absorption spectra) and the blue open stars have star-forming galaxy spectra (emission spectra). This plot demonstrates the unbiased selection of cluster members using the NIR CM relation.