FIGURE1: K-band Surface Brightness Fluctuation magnitudes vs age derived by Gonzalez, Liu & Bruzual (2004 ApJ, 611, 270) for Magellanic Cloud superclusters (obtained by coadding clusters belonging to the same SWB class - Searle, Wilkinson & Bagnuolo 1980, ApJ, 239, 803). The colour-code denotes the typical metallicity of each supercluster. The Ks data (2MASS system) have been transformed onto the Johnson system combining the relationships by Carpenter et al. (2001, AJ, 121, 2851) and Bessell & Brett (1988, PASP, 100, 1134) Theoretical SBF magnitudes for the metallicity (denoted by the appropriate colour) and age range (obtained from Gonzalez et al. 2004) of the individual superclusters are also displayed. The theoretical SBF magnitudes are obtained from our isochrones including convective core overshooting, with a mass loss parameter eta=0.2. In case of Z=0.0006 models we also show (dashed line) the predictions for a larger mass loss, i.e. eta=0.4.