Kérastase Resistance Serum Extentioniste is specially designed to protect and strengthen hair that's prone to breakage. It is lightweight and fluid enough to be left in the hair without leaving behind any residue or grease. It simply nourishes each strand deeply, fortifying your locks from the inside out. This is done with a powerful blend of ceramides and lipids, which seal the cuticle and smooth down its surface so hair looks significantly softer and more healthy.

The nourishing formula contains everything your hair needs to become noticeably hydrated and glossy. It also provides a defensive barrier across the scalp, preventing the damaging effects of external aggressors, and rids the skin of impurities.