WHAT IT IS: A Fortifying Serum for Lashe: Day Beauty - Night Care. WHAT IT DOES: Both a makeup and a treatment, an eyelash primer that deeply nourishes and strengthens the eyelashes thanks to its high-performance transparent formula combined with a new application: its beveled tip equipped with soft spikes gently massages the root of the lashes, stimulating micro circulation and the penetration of ingredients to create lashes that are denser, stronger and more resistant. At night, apply as an intensive treatment and during the day as a treatment and colorless makeup or underneath a Givenchy mascara to treat and improve the mascara's holding effect.