Differential-reddening-corrected and proper-motion-selected NIR CMD of Terzan 5. Both panels show stars located between 10” and 40” from the system’s center and satisfying stringent photometric quality criteria to ensure reliable magnitude estimates. Left: CMD reveals the double MS-TO with unprecedented clarity, definition, and stellar statistics. The superimposed boxes highlight the stars selected along the MS-TO and SGB for the age fitting of the youngest (blue shaded area) and oldest (red) population. Right: same stars shown with the best-fitting PARSEC (Bressan et al. 2012; Tang et al. 2014; Chen et al. 2015) isochrones overplotted. The adopted models correspond to ages of 12.5 Gyr (red line) and 4.7 Gyr (blue line).