Olaplex No. 9 Bond Protector Nourishing Hair Serum is a multi-benefit healthy hair styling serum, powered by Olaplex technology. This silicone-free, weightless, and antioxidant-rich serum enhances any styling routine to perfect & protect all hair types and textures.With a water-based formula, Olaplex No.9 neutralizes free-radicals, shields against pollution and other buildup, and nourishes the fiber of your hair.