I present the analysis of 10 massive early-type galaxies at $z\sim1.5$. They have been identified by means of a near-IR low resolution spectroscopic follow-up of a complete sample of 36 bright (K' $<$ 18.5) Extremely Red Objects (EROs, R-K'> 5), within a project involving other people from the Brera Observatory. On the basis of their redshift and of their bright apparent K' magnitude, it will be shown that they are the high-z counterparts of the local old massive (10^11-10^12 Mdot) early-type galaxies populating the bright end of the local luminosity function of galaxies. I will discuss the comparison of their spectro-photometric properties with a grid of synthetic models and the analysis of the 4000\AA\ break, suggesting that the field massive early-type galaxies formed the bulk of their stellar mass at 2<z<4, most likely over a short (< 1Gyr) star formation time scale.