Olaplex No 3 Hair Perfector Pre Shampoo Reparative Treatment is developed with patented bond building technology to noticeably repair extreme damage and helps to fix dry, brittle hair into soft, shiny and resilient hair. This concentrated treatment contains an exclusive ingredient Bis-aminopropyl diglycol dimaleate that works at molecular level to dramatically improve hair strength, repair damage and protect hair. Hair is made up of the fibrous protein keratin and held together by bonds. Hydrogen and salt bonds are physical bonds and are easily reformed by changes in pH, water and/or heat, while disulfide bonds are chemical covalent bonds that give hair its structure, strength and stability. When hair is subjected to heat styling, color or chemical treatments, brushing, tugging or weather, these bonds can break causing damage. This pre-shampoo treatment is proven to repair and strengthen hair from the inside out, is suitable for all hair types and can be used alone or paired with a complementary treatment for maximum at-home repair.