Nioxin Pro Clinical's System Kit 4 is designed for dry, damaged, coloured hair with progressed thinning. Clinically and dermatologically tested, this complete scalp & hair thickening system thickens and strengthens your hair against breakage while providing colour protection. 8 out 10 users saw thicker, fuller hair in 30 days! Formulated with a powerful blend of niacinamide, biotin and caffeine to help nourish the hair root, stimulate hair follicles and strengthen the hair. The three-step regimen begins with the Scalp + Hair Shampoo. Start by applying it to wet hair, gently massaging it into the scalp and hair for one minute before rinsing thoroughly. This gentle cleanser works to remove buildup, including follicle-clogging sebum and environmental residues, preparing the scalp for the next steps. Next, apply the Scalp + Hair Conditioner. Distribute it evenly throughout the hair and scalp, leaving it on for 1-3 minutes. Rinse thoroughly. This conditioner helps to restore moisture balance while protecting against breakage. Finally, apply the Scalp + Hair Thickening Treatment. Shake it well before applying directly to the entire scalp. Gently massage it in. Do not rinse. This Scalp + Hair Thickening Treatment delivers essential nutrients, antioxidants, and botanicals to the scalp, nourishing and protecting it against damage. It also helps to refresh the scalp and increase the volume of every strand, leaving your hair looking fuller and thicker. This treatment contains UV-protecting ingredients for the scalp and hair. For optimal results, use the complete Nioxin System Kit 3 daily.