The Extension to the INvestigation on Stellar Population In Relics (E-INSPIRE)  aims at extend in redshift, stellar mass and wavelength the current sample of UCMGs with a measured DOR from INSPIRE,  with the goal of collecting a statistically large sample of ultra-compact galaxies, looking for the most extreme relics in our Universe. Since relics are the 'building blocks' of today's giant ETGs, the E-INSPIRE project has the potential to shed light on the formation and evolution of this population of galaxies that account for more than half of the total stellar mass in the Universe and are responsible for most of its chemical enrichment.