No.4: This shampoo repairs and protects hair from everyday stresses - including damaged hair, split ends, and frizz - by re-linking broken bonds. No 4 is color-safe and proven to reduce breakage and strengthen all types of hair. No:8: AllOLAPLEXproducts contain ourpatented bond-building technology, strengthening fragile bonds with every step of the routine for thehealthiest hair possible. That same revolutionary technology is now infused in an at-home mask treatment for all hair types. All hair is unique, but all damage is the same. Whether it's from chemical processes, heat and styling, ponytails and brushing, or a harsh environment; damaged hair means damaged bonds. The result is hair that is dry, dull and less than manageable. OLAPLEX No.8 BOND INTENSE MOISTURE MASKis a multi-benefit, reparative mask thatMOISTURIZES, SMOOTHS, ADDS BODY & SHINE. Hair so visibly healthy, you can skip the styling.