Olaplex N 4 Bond Maintenance Shampoo is a brightening shampoo for all hair types: it's the only professional shampoo that guarantees a reconstructive action on hair. It restores strength and internal hydration to the hair for incredible shine and manageability. Olaplex N4 is the shampoo that lets you restructure your hair at home, not just during salon treatments! Formulated with the exclusive ingredient Bis-Aminopropyl Diglycole Dimeleate, Olaplex N4 restores the hair's strength and internal hydration for incredible shine and manageability. The patented active ingredient Olaplex makes each of the products, including this shampoo, the only ones in the world capable of reconnecting the sulfur bridges (disulfide bonds) broken inside the hair following coloring, heat, continuous exposure to chemicals and various mechanical stresses.