Median Einstein radius as a function of the total galaxy mass. The results refer to a source redshift of z_s = 6. We use different symbols and colors to display the differences between the data sets. The error bars show the 99% confidence intervals of the median, computed by bootstrapping the Einstein radius measurements in bins of different sub-halo masses. The horizontal dashed line shows the threshold below which secondary critical lines do not contribute to the GGSL cross sections in our analysis.