Nioxin System 4 Cleanser & Scalp Therapy Liter Duo is the ultimate choice for chemically treated and noticeably thinning hair. This duo is specially formulated to restore density, heal the scalp, moisturize, and provide structure to damaged hair strands. Nioxin uses state of the art technology to get you to your best hair yet.Complete professional thickening treatment for colored hair with progressed thinning. Provides a refreshed scalp environment