For noticeably thinning hair. 9 out of 10 people perceive an increase in hair density.* This product is a conditioner that restores the moisture and resilience in the scalp skin and hair. BioAMP adds thickness from inside the cuticle and strengthens the hair shaft. Glyco-Color Shield provides clinically proven** color protection for hair and helps safeguard the scalp from the drying effects of chemical services. Unique Scalp Access delivery system helps protect nutrients as they provide moisturizing nourishment to the scalp and hair. *Refers to thickness of hair strand and is based on consumer perception using entire Nioxin System 4 (cleanser, scalp therapy and scalp treatment).