Nioxin System 4 Scalp Treatment, noticeably thinning, fine chemically treated hair. Volumizing leave-on treatment with antioxidants & botanicals, provides a refreshed scalp environment. SPF 15 sunscreen to help protect the exposed scalp from the sun. Technologies - Scalp Access Delivery System with vitamins, botanicals, SPF 15 sunscreen, and purifying agents to help clean away follicle-clogging sebum and environmental residues from the scalp, while helping provide sun protection for the scalp. - BioAMP with cystine amino acids, and lightweight conditioning and treatment ingredients; helps provide thicker-looking hair by increasing the fullness of each hair strand, and reducing hair loss through strengthening against damage and breakage. - Glyco-Shield for chemically-treated hair and scalp with white tea extract, humectants, peppermint oil, and protective conditioning agents that deliver a dual shield technology to help provide protection and moisture balance to color-treated hair, while leaving the scalp feeling rejuvenated and refreshed.   How to use  Apply directly to entire scalp. Gently massage into scalp. Do not rinse. Use daily. May cause temporary redness to scalp after application.